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LC Sensor Rotation Detection With MSP430™ Extended Scan Interface(ESI)

Application ReportSLAA639–July 2014

LC Sensor Rotation Detection With MSP430™ ExtendedScan Interface (ESI)

ThomasKot

ABSTRACTThis application report describes the implementation of a flow meter using the Texas InstrumentsMSP430FR6989 microcontroller with the Extended Scan Interface (ESI) module. This module can providea contactless sensing approach to detecting a rotating disc. The number of rotations of the disc indicatesthe volume flow of gas or water and can be used to calculate the fee for the user. This application is goodfor gas or water meters. This application also includes the necessary information with regard to softwareand hardware procedures for the Water Meter Reference Design for two LC Sensors, Using ExtendedScan Interface (ESI) (TIDM-LC-WATERMTR).

The software described in this app note can be downloaded from http://www.ti.com/lit/zip/tidc583.

Topic ........................................................................................................................... Page

1 Introduction ........................................................................................................ 22 Working Principle of LC Sensors ........................................................................... 23 Hardware Implementation With ESI ........................................................................ 64 Software Implementation ...................................................................................... 85 Runtime Calibration With AFE2 ............................................................................ 176 Demo and Operation........................................................................................... 197 References ........................................................................................................ 268 Schematics........................................................................................................ 26

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TrademarksMSP430 is a trademark of Texas Instruments.All other trademarks are the property of their respective owners.

1 IntroductionThe TIDM-LC-WATERMTR design uses the EVM430-FR6989 evaluation module and the MSP430FR6989device to demonstrate the function of the Extended Scan Interface (ESI), which is designed for flowmeters with a rotating disc to measure the flow rate. The ESI is good for LC, reed switch, GMR, andoptical sensors. The MSP430FR6989 is an ultra-low-power MCU with up to 128KB of FRAM for code anddata. Peripherals include RTC, ADC12, CRC, AES256, MPY32, eUSCI for communication, Comp_E fortouch key module, an LCD controller, and six timers. Figure 1 shows a block diagram of the EVM,including all of the elements in the default EVM and potential add-on modules that can be added.

The main board of the EVM consists of an RF socket, a USB connection, and a dc-dc converter for thebattery power. The RF module is turned off most of the time and is turned on only a few times per day fortransmission of data. While the RF module is turned on, extra power is required. The dc-dc converter canoutput enough power to supply the module with high efficiency. All I/O ports are connected to a pack ofthrough-holes on the PCB of the EVM. With these connections, the designer can add extra flow meterfeatures like NFC/RFID for prepayment or a motor driver for valve control. A motor board is also providedto drive a rotor disc to emulate the rotating disc in flow meter. A sensor board with an LC sensor, GMR, oroptical is also provided. In this application note, the LC sensors are used. The application code can bereused for other type of sensors.

1.1 System Block Diagram

Figure 1. System Block Diagram

2 Working Principle of LC SensorsThe LC sensor consists of an inductor and a capacitor. In the application circuit, 220 pF for the capacitorand 470 µH for the inductor are used. After the capacitor is charged by a short pulse of period in 1 µs, theLC sensor starts oscillating with a frequency of 500 kHz, and the signal voltage level decays. Varying withthe inductor and capacitor used, the frequency and decay rate can be varied according to the ambientenvironment, like temperature and humidity. In this application note, room temperature is assumed.

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When there is a metal approaching the oscillating LC, the signal decays faster due to the energyabsorption by eddy current of the metal part. As shown in Figure 2, by using this characteristic, the LCsensor is used to identify metal (signal in red) or nonmetal part (signal in blue). A disc that is half coveredby metal and half by nonmetal can be constructed as a moving component to detect the flow rate. Therotation speed of the disc can then be detected by the LC sensor.

Figure 2. Oscillation Signal of Detection of Metal And Nonmetal Portions of the Rotor Disc

When overlapping these two oscillating signals of metal and nonmetal, the signal level difference of themis not constant. It starts from a small level to a largest difference in somewhere in the middle part of thesignals and then decreasing to zero. For a maximum detection distance, only the portion of signals withmaximum difference in signal level is measured (see Figure 3). This needs a timer to form a time delaybefore comparing these two signals.

Figure 3. Maximum Difference Along the Decaying LC Signal

To detect the metal and nonmetal signals, the EVM needs a reference signal with a voltage level be set inbetween the "red" and "blue" of the LC signals. In the ESI module, a DAC with 12-bit resolution isprovided for this function. For analog hysteresis, two voltage references are provided from the DACmodule of the ESI (see Figure 4). A comparator is then used to identify the metal and nonmetal parts ofthe disc.

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There are two possible positions to place the reference level, the upper range or the lower range of the LCsignal. In the ESI, the operating voltage for the comparator is from VSS to VCC – 1 V, and the operatingvoltage for the DAC is from VSS to 0.8 VCC. VCC is usually below 3.3 V. With these electrical characteristics,if the measurement uses the upper range of the oscillating signal, a time delay is needed to wait until theLC signal has decayed to below VCC – 1 V. However, when using the lower range of the signal, it can startfunctioning from VSS up. This eliminates the need for a long delay in the beginning part of the signals. Inthis EVM, the lower range is used (see Figure 4). The signal level of a sensor is measured with thevoltage level of the selected peak of its LC signal, which varies from metal to nonmetal.

Figure 4. Reference Voltages for Detection of LC Signal to Identify Metal and Nonmetal Parts

Two LC sensors are used for the detection of both clockwise and counterclockwise rotation. In a flowmeter, such as a water meter, there is a bounce back of water flow when the tap is closed. This makesthe rotor disc turn backward and forward repeatedly before the flow rate becomes zero. To eliminate thecounting error with a single sensor, two sensors can count the number of rotations for both directions andgive a correct result.

In Figure 5, a logic low is output when the sensor detects the metal part, and a logic high is output whenthe sensor detects the nonmetal part. The two sensors are located in 90° apart. Therefore, the signal ofone sensor is always 90° out of phase to the other sensor. This configuration gives four states of the twosensors: 00, 01, 11, and 10. The sequence of these four states provides direction of rotation.

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Figure 5. Logical Signal Output of Comparator of ESI for Two Sensors

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Hardware Implementation With ESI www.ti.com




3 Hardware Implementation With ESIFigure 6 shows the block diagram of the ESI. There are three clock sources, ACLK of 32768 Hz, a built-ininternal oscillator (ESIOSC) of ESI for a high-frequency clock source, and the SMCLK using the DCO. Inthe EVM, ACLK and ESIOSC are used.

Figure 6. Block Diagram of the ESI

There are two analog front ends, AFE1 and AFE2. AFE1 provides VCC/2 as the ac ground of the LC signaland an excitation circuit to provide a short pulse in the range of microseconds for the excitation of LCoscillation. Up to four sensors can be connected to the four channels of the ESI. For each channel, thesensors are excited one by one.

The input signal of a sensor is connected to the positive input of a comparator. The negative input isconnected to the 12-bit DAC. Two registers of the DAC for each channel provide two reference levels toimplement hysteresis that avoids signal oscillation in the output of the comparator.

The 32 registers of the Timing State Machine (TSM) provide the timing sequence to control the on and offof the internal parts of the ESI module. The output of the comparator for each channel is stored in aregister of the Preprocessing Unit (ESIPPU). After the completion of one cycle of measurement for allsensors (using two sensors in this EVM), an ESISTOP signal is generated to trigger the operation ofProcessing State Machine (PSM) to analysis the rotation direction and count the rotation number. Themaximum number of processing channels is three out of four selectable channels. The channels areselected in ESIPPU, and their outputs are processed by PSM.

The AFE2 has DAC registers and a comparator. The inputs to the AFE2 share the same channelsselection circuit of AFE1. With this configuration, the AFE2 measures the same signal that is beingmeasured by AFE1. The outputs of AFE2 are stored in the ESIPPU. This design enables AFE2 to be themirror of AFE1 and to perform a runtime recalibration of AFE1 without interfering with the normal operationof AFE1.

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3.1 Rotor Plate and Detection DistanceThe rotor plate or disc is used to detect the flow rate. This is a round disc that is half covered with metaland half covered with nonmetal. For a reasonable detection distance, the metal area cannot be too small,because a larger metal area has more absorption rate of the magnetic energy from the inductor of the LCsensor. The detection distance also relies on the concentration of the magnetic field from the inductor.When the disc is rotating, the LC sensor gives a large signal in the nonmetal part and a small signal in themetal part. The signal level is a continuous change from high to low and low to high. When the sensor islocated in between the metal and nonmetal area, the signal is also between the maximum and minimumlevels (see Figure 7).

Figure 7. Signal Levels From Two Sensors

Each sensor signal has a 90° phase angle from the other. When the rotor disc rotates in clockwisedirection, sensor 2 detects a high signal level when it is in the middle of nonmetal portion, and the signallevel gradually decreases to a low level when detecting the middle of the metal portion.

There are two voltage references from DAC. When signal is in high level, the lower voltage reference isused, interpreting with logic high. As the rotor disc is rotating, the signal level changes from high to low,then low to high, and repeats continuously. A logic low results when the signal is lower than the lowerreference. At the same time, the voltage reference is switched to the upper voltage reference to formanalog hysteresis. It has logic high again only when the signal level is higher than the upper voltagereference. Similarly at this time, the voltage reference is switched to lower voltage reference.

Four states (11, 01, 00, and 10) are obtained, and each state occupies the same period of time. If thesensors are not placed 90° apart, some states have a shorter time period. This implies that a highersampling rate is required to detect them, which increases power consumption.

The maximum detection distance is obtained with a large area of metal portion and an inductor designedto concentrate the magnetic field on to the metal area. Sensors have to output 90° phase angle. For amaximized solution, the rotor disc must be half covered with metal and half with nonmetal.

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4 Software ImplementationFigure 8 shows a flowchart of the default software that is provided with the EVM.

Figure 8. Flowchart of the EVM Software

4.1 Operation of SoftwareThe software is optimized to reduce power consumption of the system (see Figure 8). It starts withinitialization which includes ports setting for low current leakage, LCD, ESI internal oscillator calibration,ESI registers, sampling rate, timing state machine (TSM) with auto-TSM calibration, optimal DAC level,and processing state machine (PSM) table setting. After initialization, the EVM works well in low-powermode with the ESI and LCD as the only modules that are actively running.

To avoid too many interrupts to wake up the CPU, the Q6 flag in PSM table is used. This flag is set onlywhen the rotor disc is rotating. The system is in LPM3 mode when there is no rotation. To further lowerthe power consumption, the designer can disable the LCD and add a key button to wake up the LCDwhen reading is necessary.

For stable operation throughout the life time of the system, runtime recalibration for tracking the drift of thesensors and system is provided. A timer with variable constant "Time_to_Recal" is used to count theperiod for recalibration. The software is design to operate two sensors. For easy description in thisdocument, only the first channel or channel 0 is mentioned. The second channel works in a similar way.

4.2 InitializationPort and LCD setting for low-power operationTo enable low power consumption during ESI operation, the CPU wakes only on interrupts. In normalstate, the rotor disc is not rotating and no interrupt is generated. Q6 of the PSM in normal running modeand the ESISTOP flag during runtime recalibration mode are the only interrupt flags that wake the CPU.

All ports must be set to minimize low leakage. Unused pins should all be set to output zero.

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Port 1.2 is used as ADC input for the key pad. This port pin is set to be input mode with the pullup resistorenabled.

For Port 9 pins that are multiplexed with ESICH0 to ESICH3, all P9SEL0 and P9SEL1 register bits mustbe set to 1 for the operation of the ESI function, even when working with two channels. At the same time,the peripheral comparator has pins multiplexed with ESI. The port disable register must be set to preventparasitic current during the transition level of the gates in the port pins. To disable the port, CECTL3 mustbe set to 1.

In the application code, the LCD is always on. To further lower the power consumption, it is suggested toturn the LCD off and to turn it only for reading.

4.3 ESI Internal Oscillator CalibrationThere are three clock sources associated with the ESI: ACLK, SMCLK, and the internal oscillator of ESI.The internal oscillator and the SMCLK are the sources of high-frequency clocks which could be used inthe TSM timing control. For low power and standalone operation of ESI, the internal oscillator is preferred.However, this clock frequency varies from device to device, so an initial calibration is required. Thecalibration code can be found in ESI_ESIOSC.c.

4.4 Sensor Sampling Rate SettingFor normal operation, the sampling rate of ESI is the frequency of triggering a LC oscillation so as todetect the position of the sensors over the rotating disc. The register used is ESITSM. The equation todetermine the rate is as follows:

Sampling Rate = Maximum Rotation Rate × Number of Samples per RotationNumber of Samples per Rotation = 2 × 360 / (Angle of smaller portion of the Disc – Angle of sensorpair)

In the half metal, half nonmetal rotating disc, the angle of smaller portion is 180°. The angle of sensor pairis 90°. The detection area is then the difference between these number which is 90°. There are twosamples in this area to make sure it is detected (see Figure 9a). For one complete rotation, the number ofsamples are determined. The sampling rate is found by multiplying this number by the maximum rotationrate. Therefore, if a maximum rotation rate is 50 rotations per second, the required sampling rate is 400Hz. In the code of reference design, 500 Hz is used.

Figure 9. Sampling Rates

For runtime recalibration to determine the signal level of sensors, a faster sampling rate is required toenable the recalibration algorithm to be completed within a certain period of time. For example, arecalibration process is triggered when a sensor reaches the middle part of nonmetal area. For amaximum rotation rate of 50 per second, sampling rate of 2000 is required to complete the process with 5samples in one eighth of a rotation (see Figure 9b). In the reference code, 2340 Hz is used. The equationis as follows:

Sampling Rate = Number of Samples / Time for recalibration

Time for recalibration = 1 / Maximum Rotation Rate / 8

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4.5 Auto-TSM CalibrationThe Timing State Machine (TSM) is to control the timing of each state and the registers used areESITSMx. Referring to the user guide, the 5 most significant bits of the register are to determine theperiod of time for the corresponding state to last for. Afterwards, the TSM jumps to the next state.Repeating this process until the ESISTOP bit is set to complete one TSM cycle. An ESISTOP flag isgenerated and the TSM is repeated after waiting for a time interval of one sampling period. (An autorepeating setting is used in this reference code. However the TSM can be set to be restarted by softwarecontrol).

The following is the initial setting of TSM registers.ESITSM0 = 0x0400; // DAC=off, CA=off, 1xACLKESITSM1 = 0x202C; // DAC=off, CA=off, 5xESICLK, excitationESITSM2 = 0x0404; // DAC=off, CA=off, 1xACLKESITSM3 = 0x0024; // DAC=off, CA=off, 1xESIFCLK, delay tunableESITSM4 = 0x0024; // DAC=off, CA=off, 1xESIFCLK, delay tunableESITSM5 = 0x0024; // DAC=off, CA=off, 1xESIFCLK, delay tunableESITSM6 = 0x0024; // DAC=off, CA=off, 1xESIFCLK, delay tunableESITSM7 = 0x0024; // DAC=off, CA=off, 1xESIFCLK, delay tunableESITSM8 = 0x0024; // DAC=off, CA=off, 1xESIFCLK, delay tunableESITSM9 = 0xF134; // DAC=on, CA=on, 31xESIFCLK,ESITSM10 = 0x5974; // DAC=on, CA=on, OUTPUT LATCHES ENABLED, 12xESICLKESITSM11 = 0x0400; // DAC=off, CA=off, 1xACLCK, internally dampedESITSM12 = 0x0400; // DAC=off, CA=off, 1xACLCK, internally dampedESITSM13 = 0x20AD; // DAC=off, CA=off, 5xESICLK, excitationESITSM14 = 0x0485; // DAC=off, CA=off, 1xACLKESITSM15 = 0x00A5; // DAC=off, CA=off, 1xESIFCLK, delay tunableESITSM16 = 0x00A5; // DAC=off, CA=off, 1xESIFCLK, delay tunableESITSM17 = 0x00A5; // DAC=off, CA=off, 1xESIFCLK, delay tunableESITSM18 = 0x00A5; // DAC=off, CA=off, 1xESIFCLK, delay tunableESITSM19 = 0x00A5; // DAC=off, CA=off, 1xESIFCLK, delay tunableESITSM20 = 0x00A5; // DAC=off, CA=off, 1xESIFCLK, delay tunableESITSM21 = 0xF1B5; // DAC=on, CA=on, 31xESIFCLKESITSM22 = 0x59F5; // DAC=on, CA=on, OUTPUT LATCHES ENABLED, 12xESICLKESITSM23 = 0x0200; // stop

The corresponding LC signal of channel 0 is shown in Figure 10.

At point 1, the TSM starts with ESITSM0 of 0x0400 which is the beginning state of TSM cycle. This stateis to synchronize with the rising edge of ACLK. This ensures the following timing of states to be the samefor every TSM cycles.

At point 2, ESITSM1 is to make an excitation pulse for the channel 0 with timing last for 5 clock of ESIinternal oscillation. The length of the pulse must be long enough to ensure the first shot of oscillation toreach the voltage of VCC + Vdiode ( an internal protection diode of I/O). This makes every oscillationidentical.

At point 3, the LC sensor starts oscillating and its signal amplitude is getting smaller. ESITSM2 last for 1ACLK. An additional delay with high frequency clock from ESI oscillator is turned on to fine tune the delaytime and last for a period which is the sum of the time delay from ESITSM3 to ESITSM8. By usingESITSM2 to ESITSM8, an auto TSM time delay function "TSM_Auto_cal()" is constructed to tune the timedelay of the LC signal, so as to reach an optimal signal level and timing to capture a signal ( in point 5).This function is to add on one high frequency clock cycle delay every time. The captured signal is thenmeasured by a function "FindDAC()" to find its voltage level, by using the comparator and the DAC asreference voltage. With this setting, only the peak level is measured. In the reference design, an inverter isenabled to invert the output of comparator so that the crisis of LC signal is measured. If plotting the valueof the measured level into a graph, an envelope of the signal with a stair-case-shaped curve is obtained.when the signal level has reached the pre-defined level "LC_Threshold_TSM_CAL", an optimal delay isobtained at a point which is the mid-way to the next crisis.

At point 4, ESITSM9 is to turn on the comparator and DAC output. A proper delay is taken for the settlingtime.

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At point 5, ESITSM10 is to latch in the output of comparator and stored in ESIPPU. One of function ofhigh frequency clock delay from ESITSM3 to ESITSM8 is to select a mid-point between two peaks or twocrisis for triggering the latch in function. The selection of mid-point provides the maximum margin of phasenoise to detect the peak of the LC signal.

At point 6, ESITSM11 and ESITSM12 switch off the comparator and DAC. They also provide two ACLK oftime for internal damping of the LC sensor of channel 0, by shorting the sensor. This makes sure that itdoes not keep oscillating and induce crosstalk noise to the next channel.

From ESITSM13 to ESITSM22 is repeating the same process for channel 1. ESITSM23 generates a stopsignal to complete the TSM cycle.

Figure 10. Different States Along an LC Signal

4.6 Optimal DAC Voltage Level SettingThe DAC in the ESI generates a reference voltage for the comparator. To eliminate or reduce theoscillation when the voltage of input signal is close to voltage reference of DAC, two DAC registers"ESIDA1R0" and "ESIDAC1R1" are used to provide two reference voltage for analog hysteresis. This isespecially important when the sensor is on the border line of metal and nonmetal part of the rotor disc.The issue is how large should it be for the separation of these two levels. If the separation is small,oscillation may frequently occur. If it is too large, it increases the voltage difference required between themaximum and minimum of sensor signals and, in turn, reduces the detection distance.

Noise level of signal is then a significant data for the optimal setting of analog hysteresis. With a closerlook to the sensor signal (see Figure 11) there is a small noise when the sensor is located onto either themetal or nonmetal part of the disc. This noise can be measured wherever the signal level is. As noiseamplitude is within the "Noise Level", seldom exceeding it, the optimal hysteresis setting can then be setas the mid-level between the maximum and minimum of signal plus and minus the noise level.

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ESIDAC1R1 = (Max_DAC_Ch0 + Min_DAC_Ch0)/2 + Noise_level; // "+" for INV version, "-" for nonINV versionESIDAC1R0 = (Max_DAC_Ch0 + Min_DAC_Ch0)/2 - Noise_level; // "-" for INV version, "+" for nonINV version

Figure 11. Noise Level of Signal Determines Values of Two Reference Voltages of DAC

The noise level is measured when the rotor disc is not turning. The function "Find_Noise_level()" isresponsible for this measurement, in which "FindDAC_Fast_Range()" is the algorithm to search for thesignal level. This function is to measure the variation of signal for 0.5 second with the sensors staying atthe same position over the disc. The noise level is then the difference between the maximum andminimum of the measured data.

The Max_DAC_Ch0 and Min_DAC_Ch0 of channel 0 are respectively the maximum and minimum valueof the sensor signal with the rotor disc rotating. To measure these two data, in the function "Set_DAC()",the rotor must be rotating for 1 second, making sure the metal and nonmetal part of the disc aremeasured. The channel 1 is also going through the process at the same time.

To ensure the data correctly measured, the axis of rotor disc must be mounted tightly and in aperpendicular position in reference to the senors. If it is loosely mounted, the minimum of the signal variesbecause of the varying distance between the sensors and the metal part of the disc. For nonmetal part,there is no such variation (see Figure 12a).

To increase the difference between the maximum and minimum of the signal, a metal with higher energyabsorption rate can work. From the testing, stainless steel has better absorption rate than copper, whilecopper is better than aluminum (see Figure 12b).

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Figure 12. Signal Levels

4.7 Processing State Machine (PSM)The function of PSM is to process the input from ESIPPU so as to detect the position of the sensors onthe rotor disc and then increase or decrease the rotation counters ESICNT0, ESICNT1 and ESICNT2when the rotor disc is rotating. ESICNT0 is to record the number of rotation when the rotor disc is rotatingin clockwise direction, in parallel to the direction of water flow, while the ESICNT2 is for anti-clockwiserotation. ESICNT1 is the resultant number of rotations, which records the data equivalent to ESICNT0 –ESICNT2. Interrupt flags can be set on Q6 and Q7 of the PSM vector. There are some other interruptsettings with the outputs of the counters. The family user's guide (SLAU367) explains them in more detail.In this application code, only the Q6 of PSM vector is used for the interrupt call.

There are two channels, Ch0 and Ch1. The sensors for these channels report their detection in a timelymanner according to the sampling rate. When the rotor disc is rotating, there generates four inputsnamely: 00, 01, 11 and 10 (see Figure 13). At the same time, the position of sensors over the rotor disccan be determined. Four states are used to represent the location of the sensors, namely: S0, S1, S2, andS3, with S0 indicating both sensors are on metal part; S1 for Ch0 on nonmetal and Ch1 on metal; S2 forboth sensors on nonmetal part; and S3 for Ch0 on metal and Ch1 on nonmetal part. The direction ofrotation can then be found by processing the sequence of the states.

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Figure 13. Different States of LC Sensors When Rotor is Rotating

4.7.1 State DiagramA state diagram can then be used to clearly show the flow of the states (see Figure 14) with differentinputs and outputs. At the starting of the ESI module, the sensors are located at one of the four positionsover the rotor disc and a state is given. If the disc is not rotating, there the sensor input does not changeand the same state is kept. The output is 0. For this description, assume that the initial state is S0. Thenonrotating disc makes the sensors have 00 as input to the PSM. The state is be kept in S0 and theoutput is 0.

When the rotor is rotating clockwise, the state diagram flows from S0 to S1, S1 to S2, S2 to S3, S3 to S0,with inputs of 01, 11, 10, and 00, respectively, and continuously repeats this sequence as it keepsrotating. At the same time, the state diagram also outputs 1 when there is a state change. This increasesthe counters ESICNT0 and ESICNT1 by 4 for a complete clockwise rotation.

Figure 14. State Diagram of Two Sensors

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When the rotor disc is rotating in an anti-clockwise direction, the state diagram flows in the other direction,from S0 to S3, S3 to S2, S2 to S1, S1 to S0, with inputs of 00, 11, 01, and 10, respectively, and continuesto repeat this sequence when it keeps rotating. The output is -1 for each change of state, which decreasesthe counts ESICNT1 and ESICNT2 by 4 for a complete anti-clockwise rotation.

This state diagram includes a feature to adjust to vibration of the rotor disc. Assuming that the disc isrotating in clockwise when water is flowing, the counter increases in this direction. However, there is abouncing back of water when the tap is closed. A backward flow causes the rotor to rotate in an oppositedirection, and the state diagram reduces the counters accordingly. In the critical moment when the wateris flowing forth and backwards rapidly, the counters have to count up and down without missing a singlecount.

The state diagram also provides a state change when there is an error input, for example, from S0 to S2or S1 to S3. This can happen when the rotation speed is too high for the sample rate or when there is anerror from the sensor input. To eliminate the error input, the sampling rate must be set high enough inreference to the maximum rotation speed. In addition, proper noise level and DAC level settings arerequired. If there has error input from a sensor, the error state simply outputs 0, which does not affect thecounter, and quickly returns to the normal state. The worst case would miss two counts if it does not goback to the previous state. In this application code, there is no extra error handling for this type of error.However, Q7 of the PSM table is defined for generating an interrupt flag for this error. If designers need tobuild a dedicated error handling code, an interrupt is needed. Designers have to enable the interruptenable bit for their interrupt coding.

4.7.2 State Diagram to State TableTo convert the state diagram into a PSM table (see Table 1), S0 to S3 must be given a code. Put S0 = 00,S1 = 01, S2 = 11, and S3 = 10. In the PSM table, Q0 to Q7 represent the bit number of the register. Thenext state is represented by Q3 and Q0; the output is set by Q1 and Q2. When Q1 is set, the ESICNT0and ESICNT1 are increased by 1. When Q2 is set, the ESICNT1 is decreased by 1 and ESICNT2 isincreased by 1. Q7 is set when there is an error input, indicated with red highlight in Table 1. Q6 is setwhen there is a state change in a clockwise direction, indicating with blue highlight in Table 1. Q4 and Q5are not used in the application code.

The Q6 is another interrupt flag of PSM table. In the application code, when Q6 is set, it triggers aninterrupt code to update the LCD display. This is a design for low power consumption for CPU being inidle mode when the rotor disc is not rotating.

Table 1. State Table Converted From State Diagram

Present State of ESI Input Output Next State Interrupt to haveCh1 Ch0 Q2 (-1) Q1 (+1) Q3 Q0 Q7 Q6

0 0 0 0 0 0 0 0 0 00 0 0 1 0 1 0 1 0 10 0 1 0 1 0 1 0 0 00 0 1 1 0 0 1 1 1 00 1 0 0 1 0 0 0 0 00 1 0 1 0 0 0 1 0 00 1 1 0 0 0 1 0 1 00 1 1 1 0 1 1 1 0 11 0 0 0 0 1 0 0 0 11 0 0 1 0 0 0 1 1 01 0 1 0 0 0 1 0 0 01 0 1 1 1 0 1 1 0 01 1 0 0 0 0 0 0 1 01 1 0 1 1 0 0 1 0 01 1 1 0 0 1 1 0 0 11 1 1 1 0 0 1 1 0 0

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By rearranging the bit order in Table 1, the PSM table is formed as Table 2.

The Hex values are then put into the code and stored in the RAM of PSM.

Table 2. PSM Table by Rearrangement of Bit Order of the State Table

Error Flag RotationFlag Rearrangement of Bit Order

Hex ValueQ7 Q6 Q5 Q4 Q3 Q2 Q1 Q00 0 0 0 0 0 0 0 0x000 1 0 0 0 0 1 1 0x430 0 0 0 1 1 0 0 0x0C1 0 0 0 1 0 0 1 0x890 0 0 0 0 1 0 0 0x040 0 0 0 0 0 0 1 0x011 0 0 0 1 0 0 0 0x880 1 0 0 1 0 1 1 0x4B0 1 0 0 0 0 1 0 0x421 0 0 0 0 0 0 1 0x810 0 0 0 1 0 0 0 0x080 0 0 0 1 1 0 1 0x0D1 0 0 0 0 0 0 0 0x800 0 0 0 0 1 0 1 0x050 1 0 0 1 0 1 0 0x4A0 0 0 0 1 0 0 1 0x09

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www.ti.com Runtime Calibration With AFE2




5 Runtime Calibration With AFE2When a flow meter is installed, it is expected to run for many years until the battery is drained. Due toenvironmental variation and component decay, the sensor signals will drift. To follow this signal drift, thereference voltages from DAC have to follow. This process requires a runtime recalibration of the system(see Figure 15). At each recalibration, the system is still working well and needs only a small calibration tofollow a small drift. With this operation, even there is a large up or down drift over a long time, this runtimecalibration keeps the DAC reference voltage at the optimal level.

As the system is battery powered, power consumption is a concern. In the ESI module, there has an extraanalog front end (AFE2) with duplicated DAC and comparator, connecting to the common sensors ofAFE1. When processing the calibration, AFE2 is switched on to measure the same signals that AFE1 isdetecting. No extra excitation of a dummy signal is required. This cuts half of the power consumption thatis required by the Scan Interface (SIF) in the MSP430FW42x series.

Figure 15. Flowchart of Runtime Recalibration

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Runtime Calibration With AFE2 www.ti.com




5.1 Operation of RecalibrationDuring the normal operation, there is a timer to activate the recalibration process. The timer intervalshould be set within a period during which a small drift expected. The designer can modify the constant"Time_to_Recal" to change the timing. The input clock for the timer is 32768 Hz.

When the process is activated, the MCU is in LPM3 mode until an interrupt is triggered by the Q6 flagfrom the PSM connected to AFE1. During recalibration, AFE1 continues normal operation, and AFE2 isturned on for signal level measurement. The Q6 flag is set only when the rotor disc is rotating in clockwisedirection and there is a change of state of a sensor. This ensures low-power operation duringrecalibration. See the flow chart of runtime recalibration in Figure 15.

As the two sensors are located in 90° apart, one sensor must be located at the center of the metal ornonmetal area of the rotor disc when the other sensor detects a change of state by AFE1 (see Figure 16).Using this property, the signal level of this sensor is always the maximum or minimum. As this ismeasured with the rotor disc rotating, the measurement algorithm is required to be fast and timedeterministic. By using the function AFE2_FindDAC_Fast_Successive() for AFE2, the signal level can bemeasured in five measuring cycles. A faster sampling rate of 2340 Hz is required to make sure that thesensor under measurement is kept on the same side of the disc and the signal level remains in a constantlevel. For sampling rate setting, see the section of sampling rate.

Figure 16. Transition States Of A Sensor

Because AFE1 and AFE2 are both inside the single MCU, the environment is identical to both of them.When there is a drift in AFE2, there is a similar drift in AFE1. Therefore, when a drift is determined inAFE2, the new level of AFE1 can be added with the same level of drift.

After four complete rotations, the recorded measurements are used to calculate the drift of AFE2 and thenew DAC level of AFE1, as follows for channel 0. similar for channel 1.

AFE2_drift0 = (AFE2_Max_DAC_Ch0 + AFE2_Min_DAC_Ch0)/2 - AFE2_base0;New_level = AFE1_base0 + AFE2_drift0;Delta = (ESIDAC1R0+ESIDAC1R1)/2 - New_level;

If "Delta", the difference between the new level and previous level of DAC of AFE1, is less than 10, a validmeasurement is confirmed and the new DAC values are set for channel 0 of AFE1, as calculated in theseequations.

The designer can modify the condition value for a validation of measurement, but it cannot be larger thanthe half of the normal separation of maximum and minimum. If the condition exceeds this value, it can betreated as noise, because the ESI is still working during recalibration, and expects a small drift.

ESIDAC1R0 = New_level - Noise_level;ESIDAC1R1 = New_level + Noise_level;

After that, the recalibration is finished. The sampling rate is changed back to normal rate and the timerrestarts for the next calibration. There is a timeout timer of two seconds during the recalibration process. Ifthe rotor does not move for two seconds, the process times out, the sampling rate is changed back to thenormal rate, and the application waits for the next calibration.

http://www.ti.com


www.ti.com Demo and Operation



LC Sensor Rotation Detection With MSP430™ Extended Scan Interface (ESI)

6 Demo and Operation

6.1 Main BoardThe main board of the EVM uses the MSP430FR6989 device with an LCD display (see Figure 17). Thisboard is powered by USB and provides 3.3 V VCC through a buck converter. It can be divided into sevenparts, which are shown in Table 3 and described in Table 3.

This board is a platform for the development of a flow meter with RF and USB connection. The applicationsoftware includes code for the ESI module for flow measurement. The default software does not havecode for connection to Part 1, Part 5, and Part 6.

Figure 17. Main Board of EVM

Table 3. Main Board Description

Part 1 A socket for RF modules of sub-1GHz or 2.4GHz, connecting to the MCU with SPI and IO. For details of RF modules,read CC1120 development kit.

Part 2 Through-holes connecting to I/O that are otherwise unconnected. The headers are the I2C connection.Part 3 The JTAG debugger and a USB HID interface. The HID interface can connect the board to PC with a dedicated GUI.Part 4 A reset button. This board does not have on/off switch. To re-start the firmware, push the reset button.

Part 5 This device contains five push-button switches. The firmware does not have code for this part. Designers can use it toimplement a key control.

Part 6 LED indicator, connected to PJ.2 and PJ.3. To reduce current consumption, remove the jumpers.Part 7 The socket for the Sensor board to connect to the ESI of the MCU.

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Demo and Operation www.ti.com




6.2 Sensor BoardThe sensor board is designed for various sensors: LC, GMR, or optical sensors (see Figure 18). On theleft part of the board, only LC sensors can be soldered on. The sensors can be placed in differentorientation. For half covered metal rotor disc, the sensors are placed in 90° apart. On the right part of theboard, GMR and optical sensors can be connected.

Figure 18. Sensor Board

6.3 Motor BoardThe motor board is to drive the rotor disc to simulate water or gas flow (see Figure 19). The battery socketis on the back of the board. The parts of the board are described in Table 4.

Figure 19. Motor Board

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Table 4. Motor Board Description

Part 1 Two pins connected to external powerPart 2 Power switch to turn the motor board on or offPart 3 2-wire Spy-Bi-Wire mode of JTAG. This can be used to program or debug the firmware.Part 4 Variable resistor to vary the rotation speed.Part 5 These buttons are to select the rotation direction and also act as a stop button.Part 6 This is an infrared sensor that provides feedback on the rotation speed of the rotor disc.Part 7 A rotor disc with half covered by copper.Part 8 A connection header for I2C and UART.

6.4 DemonstrationFigure 20 shows the complete EVM hardware set up to run the demonstration code.

Figure 20. Complete Evaluation Hardware

Procedure to use the EVM with Auto-Calibration in initialization of code:1. Set the rotor at 5 mm from the sensor board and switch off the motor.2. Power the main board with a USB cable.3. At start up, a TSM calibration starts and the LCD displays "0". Wait until the LCD displays "8888", then

go to next step.4. Switch on the motor and do not adjust the distance between rotor and sensors. A calibration that

determines the proper reference voltages for the DAC starts now and lasts for one second.5. The initial calibration is now finish. The LCD continues to display the number of rotations.

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6.4.1 Current ConsumptionFigure 21 shows the current consumption of the MCU with two LC sensors, excluding the current into theLCD, power, and other modules on the board. The data is taken by measuring the current flowing into theMCU connected to two sensors with the LCD off, varying with different sampling rate in the SIF ofMSP430FW42x and the ESI of MSP430FR6989.

Figure 21. Current Consumption of ESI With Two Sensors

From the experimental data, the current consumption in MSP430FR6989 is half of that for aMSP430FW42x system with the same type of LC sensors.• For the MSP430FR6989 with two LC sensors, the current per sample is less than 9 nA.• For the MSP430FW42x with two LC sensors, the current per sample is less than 17 nA.

Current consumption of the MSP430FR6989 running the ESI without sensors is also given. This showsthat the LC sensors account for half of the total current consumption of the system. To further reduce thecurrent consumption, well designed LC sensors are necessary.

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6.5 Signal Level Searching AlgorithmThere are two channels in the algorithm. For simplicity in the following flow charts, only the first channel isshown. The other channel is processed with the same algorithm.

6.5.1 FindDAC()Figure 22 shows the flowchart of FindDAC().

Figure 22. FindDAC() Flowchart

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6.5.2 FindDAC_Fast_Range()Figure 23 shows the flowchart of FindDAC_Fast_Range().

Figure 23. FindDAC_Fast_Range Flowchart

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6.5.3 AFE2_FindDAC_Fast_Successive()Figure 24 shows the flowchart of AFE2_FindDAC_Fast_Successive().

Figure 24. AFE2_FindDAC_Fast_Successive() Flowchart

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References www.ti.com




7 References1. MSP430FR698x(1), MSP430FR598x(1) Mixed-Signal Microcontrollers (SLAS789)

2. MSP430FR58xx, MSP430FR59xx, MSP430FR68xx, and MSP430FR69xx Family User's Guide(SLAU367)

3. Code Composer Studio (CCSTUDIO) Version 5.5

4. Rotation Detection With the MSP430 Scan Interface (SLAA222)

5. SmartRF Transceiver Evaluation Board User's Guide (SWRU294)

8 SchematicsThe following figures show the schematics of the main, sensor, and motor boards in the EVM430-FR6989.

http://www.ti.com


http://www.ti.com/lit/pdf/SLAS789

http://www.ti.com/lit/pdf/SLAU367

http://www.ti.com/tool/CCSTUDIO

http://www.ti.com/lit/pdf/SLAA222

http://www.ti.com/lit/pdf/SWRU294

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Change in menu Project|Project Options|ParametersProject Title:Designed for:Public Release

Assembly Variant: [No Variations]

?Texas Instruments 2014

Drawn By:Engineer: Enter name of project lead

Texas Instruments and/or its licensors do not warrant the accuracy or completeness of this specification or any information contained therein. Texas Instruments and/or its licensors do notwarrant that this design will meet the specifications, will be suitable for your application or fit for any particular purpose, or will operate in an implementation. Texas Instruments and/or itslicensors do not warrant that the design is production worthy. You should completely validate and test your design implementation to confirm the system functionality for your application.

Not in version controlSVN Rev:XX####Number: Rev: E1

DP01

DM02

VCC3

RESET4

EECLK5

EEDATA/GANGED6

GND7

BUSPWR8

PWRON19

OVRCUR110

DM111

DP112

PWRON213

OVRCUR214

DM215

DP216

PWRON317

OVRCUR318

DM319

DP320

PWRON421

OVRCUR422

DM423

DP424

VCC25

EXTMEM26

TSTPLL/48MCLK27

GND28

XTAL229

XTAL130

TSTMODE31

SUSPND32

EP33

U401

TUSB2046BIRHBR

MODE1

SW2

VIN3

4

EN5

FB6

GND

U403TPS62237DRYR

VCC1

NC2

IO13

GND4

IO25

U400

TPD2E001DRLR

OUT1

N/C2

NR/FB3

GND4

EN5

N/C6

N/C7

IN8

PAD

U402

TPS73533DRB (DNP)

POWER SWITCHES

GND

GND

D-

D+

MICRO USB

0.1µFC402

GND

3V3

22pFC403

22pFC404

GNDGND

GND

GND

GND

DP0

DM0

3V3

0.1µFC400

GND

HUB RESET

HUB_RESET

HUB_RESET

DP0DM0

GND

DP4

DM4

DP3

DM3

HUB3 and HUB4 NOT USED

DP3DM3

DP4DM4

GND

6MHZ XTAL

1

2

3

Q400CSTCR4M00G15L99

GND

HUB_XTAL1

HUB_XTAL1

HUB_XTAL2

0.01µF (DNP)C416

GND GNDGND

OPTIONAL 3.3V LDO

3.3V BUCK REGULATOR

NC

THERMAL CONNECTION ONLY

NC

BUCK_3V3LDO_3V3

3V3

3V3

USB HUB

3V3

500mA LDO LDO_3V3

BUCK_3V3

10pFC405

10pFC406

GNDGND

EZFET USB HUB FILTER

HUB_DM2

HUB_DP2

GND GND

10pFC410

10pFC412

GNDGNDGND GND

HUB_DM1

HUB_DP1

DM1DP1

DM2DP2

DM2

DP2

DM1

DP1

BRIDGE USB HUB FILTER

GND

4.7µFC401

2.2µF (DNP)C418

1µF (DNP)C414

1µFC417

1µFC415

GND

0.1µFC407

0.1µFC408

GND

27

R406 HUB_XTAL2

USB_SHIELD

15.0kR410

15.0kR415

15.0kR414

15.0kR411

1.5kR408

33

R405

47kR404

15.0k

R403

15.0k

R402

15.0k

R401

15.0k

R400

10k (DNP)

R418

22

R413

22

R412

22

R417

22

R416

22

R407

22

R409

1

2

3

4

5

6

7

10

11

8

9

J400

ZX62R-B-5P

2.2µHL400

NR3010T2R2M

DNP

R419

0

R420

3V3

NC

NCNCNCNC

VBUS

VBUS

VBUS

Place 0.1uF as close toU400 vcc as possible.Also ensure sufficient metalfor Vcc and Gnd for ESDconduction.

www.ti.com Schematics




Figure 25. Schematic, Main Board (1 of 4)

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P6.0/CB0/A01

P6.1/CB1/A12

P6.2/CB2/A23

P6.3/CB3/A34

P6.4/CB4/A45

P6.5/CB5/A56

P6.6/CB6/A67

P6.7/CB7/A78

P5.0/A8/VREF+/VEREF+9

P5.1/A9/VREF-/VEREF-10

AVCC111

P5.4/XIN12

P5.5/XOUT13

AVSS114

DVCC115

DVSS116

VCORE17

P1.0/TA0CLK/ACLK18

P1.1/TA0.019

P1.2/TA0.120

P1.3/TA0.221

P1.4/TA0.322

P1.5/TA0.423

P1.6/TA1CLK/CBOUT24

P1.7/TA1.025

P2.0/TA1.126

P2.1/TA1.227

P2.2/TA2CLK/SMCLK28

P2.3/TA2.029

P2.4/TA2.130

P2.5/TA2.231

P2.6/RTCCLK/DMAE032

P2.7/UCB0STE/UCA0CLK33

P3.0/UCB0SIMO/UCB0SDA34

P3.1/UCB0SOMI/UCB0SCL35

P3.2/UCB0CLK/UCA0STE36

P3.3/UCA0TXD/UCA0SIMO37

P3.4/UCA0RXD/UCA0SOMI38

DVSS239

DVCC240

P4.0/PM_UCB1STE/PM_UCA1CLK41

P4.1/PM_UCB1SIMO/PM_UCB1SDA42

P4.2/PM_UCB1SOMI/PM_UCB1SCL43

P4.3/PM_UCB1CLK/PM_UCA1STE44

P4.4/PM_UCA1TXD/PM_UCA1SIMO45

P4.5/PM_UCA1RXD/PM_UCA1SOMI46

P4.6/PM_NONE47

P4.7/PM_NONE48

VSSU49

PU.0/DP50

PUR51

PU.1/DM52

VBUS53

VUSB54

V1855

AVSS256

P5.2/XT2IN57

P5.3/XT2OUT58

TEST/SBWTCK59

PJ.0/TDO60

PJ.1/TDI/TCLK61

PJ.2/TMS62

PJ.3/TCK63

RST/NMI/SBWTDIO64

QFN PAD65

U200

MSP430F5528IRGCT

BRIDGE_DM

BRIDGE_DP

10pFC200

10pFC201

GNDGNDUSB

4MHZ XTAL

1

2

3

Q200MURATA -FILTER_CSTCR4M00G15

GND

BRIDGE_XT2IN

BRIDGE_XT2OUT

3V3

GND

CAPS

0.1µFC205

GND

3V3

0.1µFC202

0.22µFC206

GND

BRIDGE_VUSB

0.47µFC208

0.22µFC207

GND GND

BRIDGE_V18 BRIDGE_VCORE

BRIDGE_DMBRIDGE_DP

3V3

GND GND

VBUS

VBUSBRIDGE_VUSB

BRIDGE_V18BRIDGE_VCORE

3V3

GNDBRIDGE USB BSL

BRIDGE_PUR

BRIDGE_PUR

3V3

1000pFC210

GNDBRIDGE RESET

BRIDGE_PUR

EXTERNAL UART

BRIDGE_XT2INBRIDGE_XT2OUT

EXTERNAL I2C

BRIDGE_TDOBRIDGE_TDIBRIDGE_TMSBRIDGE_TCK

CONNECTS TO TARGET UART

FROM TARGET DATA RDYLEDS

Green

12

D201

GND

BRIDGE_LED0

BRIDGE_LED1

Green

12

D203

BRIDGE_LED2

BRIDGE_LED3

BRIDGE_LED0BRIDGE_LED1BRIDGE_LED2BRIDGE_LED3

HUB_DM1

HUB_DP1

MSP430F5528 COMMUNICATIONS BRIDGE

10µFC203

4.7µFC209

0.1µFC204

1

2

3

J201

TSW-103-07-G-S

BRIDGE_UCA0_RXDBRIDGE_UCA0_TXD

EXTERNAL UART

GND

BRIDGE_UCA0_RXDBRIDGE_UCA0_TXD

OPTIONAL JTAG PROGRAMMING

BRIDGE_RSTBRIDGE_TEST

BRIDGE_RST

Red

12

D200Green

12

D202

47kR209

100R211

1.0MegR210

27

R203

27

R201

1.5kR206

390R202

390R204

390R205

470R200

BRIDGE_TARGET_READY_OUT

1 2

3 4

5 6

7 8

J601

BRIDGE_TARGET_UART_RXD

BRIDGE_TARGET_UART_TXD

TARGET TO BRIDGE COMMUNICATION JUMPER

BRIDGE_TARGET_READY_IN

EXTERNAL I2C

2.2KR601

2.2KR600

3V3

GND

GNDBRIDGE_TESTBRIDGE_TDOBRIDGE_TDIBRIDGE_TMSBRIDGE_TCKBRIDGE_RST

5

4

1

2

3

6

7

J200

TSW-107-07-G-SGND

BRIDGE_UCB0_SCLBRIDGE_UCB0_SDA

BRIDGE_UCB0_SDABRIDGE_UCB0_SCL

TARGET_READY_INBRIDGE_READY_OUTBRIDGE_UCA1_TXBRIDGE_UCA1_RX

BRIDGE_UCA1_TXBRIDGE_UCA1_RX

BRIDGE_READY_OUTTARGET_READY_IN

4

1

2

3

J600

TSW-104-07-G-S

BRIDGE_UCB0_DRDY

BRIDGE_UCB0_DRDY

S201

S202

C202, C203near pin11,15

C204near pin40

C208near pin53

Schematics www.ti.com





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P6.0/CB0/A01

P6.1/CB1/A12

P6.2/CB2/A23

P6.3/CB3/A34

P6.4/CB4/A45

P6.5/CB5/A56

P6.6/CB6/A67

P6.7/CB7/A78

P5.0/A8/VREF+/VEREF+9

P5.1/A9/VREF-/VEREF-10

AVCC111

P5.4/XIN12

P5.5/XOUT13

AVSS114

DVCC115

DVSS116

VCORE17

P1.0/TA0CLK/ACLK18

P1.1/TA0.019

P1.2/TA0.120

P1.3/TA0.221

P1.4/TA0.322

P1.5/TA0.423

P1.6/TA1CLK/CBOUT24

P1.7/TA1.025

P2.0/TA1.126

P2.1/TA1.227

P2.2/TA2CLK/SMCLK28

P2.3/TA2.029

P2.4/TA2.130

P2.5/TA2.231

P2.6/RTCCLK/DMAE032

P2.7/UCB0STE/UCA0CLK33

P3.0/UCB0SIMO/UCB0SDA34

P3.1/UCB0SOMI/UCB0SCL35

P3.2/UCB0CLK/UCA0STE36

P3.3/UCA0TXD/UCA0SIMO37

P3.4/UCA0RXD/UCA0SOMI38

DVSS239

DVCC240

P4.0/PM_UCB1STE/PM_UCA1CLK41

P4.1/PM_UCB1SIMO/PM_UCB1SDA42

P4.2/PM_UCB1SOMI/PM_UCB1SCL43

P4.3/PM_UCB1CLK/PM_UCA1STE44

P4.4/PM_UCA1TXD/PM_UCA1SIMO45

P4.5/PM_UCA1RXD/PM_UCA1SOMI46

P4.6/PM_NONE47

P4.7/PM_NONE48

VSSU49

PU.0/DP50

PUR51

PU.1/DM52

VBUS53

VUSB54

V1855

AVSS256

P5.2/XT2IN57

P5.3/XT2OUT58

TEST/SBWTCK59

PJ.0/TDO60

PJ.1/TDI/TCLK61

PJ.2/TMS62

PJ.3/TCK63

RST/NMI/SBWTDIO64

QFN PAD65

U100

MSP430F5528IRGCR

GND

47kR106

150kR109

1.5kR103

1.0MegR102

VBUS

GND

3V3

1000pFC111

GND

EZFET_VREF

EZFET_V18

EZFET_VUSB

EZFET_AVBUS

33pFC110

EZFET_AVCCOUT2ADC

EZFET_DPEZFET_DM

EZFET_PUR

EZFET_TDOEZFET_TDIEZFET_TMSEZFET_TCK

EZFET_TEST

GND

EZFET_DM

EZFET_DP

GNDEZFET_TESTEZFET_TDOEZFET_TDIEZFET_TMSEZFET_TCKEZFET_RST

3V3

GND

33pFC109

TARGET VCC SENSE

EZFET_AVCCOUT2ADC

EZFET_AVBUS

VBUS SENSE

EZFET_PROGRAM/DEBUG

EZFET_RST

EZFET RESET

EZFET_RST

LEDS4MHZ XTAL

470R104

390R105

Green

12

D101Red

12

D100

GND

EZFET_LED0

EZFET_LED1

EZFET_LED0EZFET_LED1

1

2

3

Q100

GND

EZFET_XT2IN

EZFET_XT2OUT

EZFET_XT2INEZFET_XT2OUT

CAPS

GND

3V3

0.1µFC102

3V3

0.22µFC105

GND

EZFET_VUSB

0.47µFC107

0.22µFC106

GND GND

EZFET_V18 EZFET_VCORE

EZFET_VCORE

0.1µFC108

GND

EZFET_VREF

27

R100

10pFC100

27

R101

10pFC101

GNDGNDUSB

EZFET_PUR

HUB_DM2

HUB_DP2

MSP430F5528 EZFET-LITE

0.1µFC10410µF

C103

240kR110

220kR108

220kR107

5

4

1

2

3

6

7

J100

TSW-107-07-G-S

EZFET

EZFET_TARGET_TEST_SBWTCK

EZFET_TARGET_RST_SBWTDIO

EZFET_TARGET_UART_RXD

EZFET_TARGET_UART_TXD

GND TARGET_GND

3V3

TARGET_3V3

10µFC409

1µFC411

EZFET_UART_TXDEZFET_UART_RXD

EZFET_UART_RXDEZFET_UART_TXD

EZFET_SBW_RST

EZFET_SBW_RSTEZFET_SBW_TST

EZFET_SBW_TST 1 2

3 4

5 6

7 8

J402

1 2

3 4

J401

TSW-102-07-G-D

VBUS






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DNPR11

DNPR12

DNPR13

4u7C33

DNPVR1

TARGET_GND

TARGET_GND

0.1uF

C9

TARGET_3V3

TARGET_ GND

AGND

22pFC10

22pFC11

1 2

X2 DNP

DNFC12

DNFC13

AGND AGND

0.1uF

C7

0.1uF

C5

TARGET_GND

0.1uFC3

TARGET_3V3

TARGET_ GND

TARGET_3V3

AVCC

DNPR62

DNPR61

DNPR60

DNPR59

DNPC34

DNPC35

DNP

R63

TARGET_GND

AGNDTARGET_GND

P2.0/UCA0SIMO/UCA0TXD/TB0.6/TB0CLK51

P7.0/TA0CLK/S1752

P7.1/TA0.0/S1653

P7.2/TA0.1/S1554

P7.3/TA0.2/S1455

P7.4/SMCLK/S1356

DVSS257

DVCC258

P8.4/A7/C759

P8.5/A6/C660

P8.6/A5/C561

P8.7/A4/C462

P1.3/ESITEST4/TA1.2/A3/C363

P1.2/TA1.1/TA0CLK/COUT/A2/C264

P1.1/TA0.2/TA1CLK/COUT/A1/C1/VREF+/VeREF+65

P1.0/TA0.1/DMAE0/RTCCLK/A0/C0/VREF-/VeREF66

P9.0/ESICH0/ESITEST0/A8/C867




P9.4/ESICI0/A12/C1271

P9.5/ESICI1/A13/C1372

P9.6/ESICI2/A14/C1473

P9.7/ESICI3/A15/C1574

ESIVCC75

ES

IVS

S76

ES

ICI

77

ES

ICO

M78

AV

CC

179

AV

SS

380

PJ.7

/HF

XO

UT

81

PJ.6

/HF

XIN

82

AV

SS

183

PJ.4

/LF

XIN

84

PJ.5

/LF

XO

UT

85

AV

SS

286

P5.4

/UC

A1S

IMO

/UC

A1T

XD

/S12

87

P5

.5/U

CA

1S

OM

I/U

CA

1R

XD

/S11

88

P5

.6/U

CA

1C

LK

/S10

89

P5

.7/U

CA

1S

TE

/TB

0C

LK

/S9

90

P4

.4/U

CB

1S

TE

/TA

1C

LK

/S8

91

P4

.5/U

CB

1C

LK

/TA

1.0

/S7

92

P4

.6/U

CB

1S

IMO

/UC

B1

SD

A/T

A1.1

/S6

93

P4.7

/UC

B1S

OM

I/U

CB

1S

CL/T

A1.2

/S5

94

P1

0.0

/SM

CL

K/S

495

P4.0

/UC

B1S

IMO

/UC

B1S

DA

/MC

LK

/S3

96

P4.1

/UC

B1S

OM

I/U

CB

1S

CL

/AC

LK

/S2

97

DV

SS

398

DV

CC

399

P4.2

/UC

A0S

IMO

/UC

A0T

XD

/UC

B1C

LK

100

DV

SS

126

DV

CC

127

TE

ST

/SB

WT

CK

28

RE

SE

T/N

MI/S

BW

TD

IO29

PJ.0

/TD

O/T

B0

OU

TH

/SM

CL

K/S

RS

CG

130

PJ.1

/TD

I/T

CLK

/MC

LK

/SR

SC

G0

31

PJ.2

/TM

S/A

CLK

/SR

OS

CO

FF

32

PJ.3

/TC

K/C

OU

T/S

RC

PU

OF

F33

P6

.7/T

A0C

LK

/S3

134

P7

.5/T

A0.2

/S3

035

P7

.6/T

A0.1

/S2

936

P1

0.1

/TA

0.0

/S28

37

P7

.7/T

A1.2

/TB

0O

UT

H/S

27

38

P3

.3/T

A1.1

/TB

0C

LK

/S26

39

P3

.4/U

CA

1S

IMO

/UC

A1

TX

D/T

B0.0

/S25

40

P3

.5/U

CA

1S

OM

I/U

CA

1R

XD

/TB

0.1

/S24

41

P3

.6/U

CA

1C

LK

/TB

0.2

/S2

342

P3

.7/U

CA

1S

TE

/TB

0.3

/S22

43

P8

.0/R

TC

CLK

/S21

44

P8

.1/D

MA

E0

/S20

45

P8

.2/S

19

46

P8

.3/M

CLK

/S18

47

P2

.3/U

CA

0S

TE

/TB

0O

UT

H48

P2

.2/U

CA

0C

LK

/TB

0.4

/RT

CC

LK

49

P2

.1/U

CA

0S

OM

I/U

CA

0R

XD

/TB

0.5

/DM

AE

050

P4.3/UCA0SOMI/UCA0RXD#/UCB1STE1

P1.4/UCB0CLK/UCA0STE/TA1.0/S12

P1.5/UCB0STE/UCA0CLK/TA0.0/S03

P1.6/UCB0SIMO/UCB0SDA/TA0.14

P1.7/UCB0SOMI/UCB0SCL/TA0.25

R33/LCDCAP6

P6.0/R237

P6.1/R13/LCDREF8

P6.2/COUT/R039

P6.3/COM010

P6.4/TB0.0/COM111

P6.5/TB0.1/COM212

P6.6/TB0.2/COM313

P2.4/TB0.3/COM4/S4314

P2.5/TB0.4/COM5/S4215

P2.6/TB0.5/COM6/S4116

P2.7/TB0.6/COM7/S4017

P10.2/TA1.0/SMCLK/S3918

P5.0/TA1.1/MCLK/S3819

P5.1/TA1.2/S3720

P5.2/TA1.0/TA1CLK/ACLK/S3621

P5.3/UCB1STE/S3522

P3.0/UCB1CLK/S3423

P3.1/UCB1SIMO/UCB1SDA/S3324

P3.2/UCB1SOMI/UCB1SCL/S3225

U1MSP430FR6989

AGNDAGND

X132.768

NT0

Net-Tie

47KR1

2.2nFC1

MC

U_R

ES

ET

TARGET_GND

TARGET_3V3

5K6R5

5K6R6

5K6R7

5K6R8

100KR3

TARGET_3V3

11

22

33

44

55

66

77

88

99

10

10

11

11

12

12

13

13

14

14

15

15

16

16

17

17

18

18

19

19

20

20

21

21

22

22

23

23

24

24

CO

M3

25

CO

M2

26

CO

M1

27

CO

M0

28

29

29

30

30

31

31

32

32

33

33

34

34

35

35

36

36

37

37

38

38

39

39

40

40

41

41

42

42

43

43

44

44

LCD LCD

LCDFH-1152P

LED1

470RR9

LED2

470RR10

TARGET_3V3

1 2

JP13

1 2

JP14

1

2

3

4

5

6

SBW

Header 6

TARGET_GND

UART0_TXD

UART0_RXD

TEST/SBWTCKRST/NMI/SBWTDIO

RST/NMI/SBWTDIO

LC

D0

LC

D1

LC

D2

LC

D3

LC

D4

LC

D5

LC

D6

LC

D7

LC

D8

LC

D9

LC

D1

0L

CD

11

LC

D1

2L

CD

13

LC

D1

4L

CD

15

LC

D1

6L

CD

17

LC

D1

8L

CD

19

LC

D2

0L

CD

21

LC

D22

LC

D23

LC

D24

LC

D25

LC

D26

LC

D27

LC

D28

LC

D29

LC

D30

LC

D32

LC

D33

LC

D34

LC

D35

LC

D36

LC

D37

LC

D38

LC

D39

LC

D31

CO

M0

CO

M1

CO

M2

CO

M3

LCD28LCD29LCD30LCD31LCD32LCD33LCD34LCD35LCD36LCD37LCD38LCD39

COM0COM1COM2COM3

LCD0LCD1

LC

D2

LC

D3

LC

D4

LC

D5

LC

D6

LC

D7

LC

D8

LC

D9

LC

D1

0L

CD

11

LC

D1

2

LCD13LCD14LCD15LCD16LCD17

LC

D1

8L

CD

19

LC

D2

0L

CD

21

LC

D2

2L

CD

23

LC

D2

4L

CD

25

LC

D2

6L

CD

27

TE

ST

/SB

WT

CK

RS

T/N

MI/S

BW

TD

IOP

J.0

LE

D1

LE

D2

BUT_AIN

BUT_AIN

ESITEST4

ESICI0ESICI1ESICI2ESICI3

ESICH1/ESITEST1ESICH2/ESITEST2ESICH3/ESITEST3

ESICH0/ESITEST0

ESICOM

ESIVSS

ESIVCC

ES

IVS

SE

SIC

IE

SIC

OM

ESIVCC

LED1

LED2

UART0_RXD

UA

RT

0_

TX

D

I2C_SDAI2C_SCL

RF_RESETRF_GPIO_81RF_GPIO_10RF_GPIO_82

RF_GPIO_17RF_GPIO_13

RF_SPI1_MOSI/RF_UART_RXD

RF

_S

PI1

_M

ISO

/RF

_U

AR

T_

TX

DR

F_

SP

I1_S

CLK

RF

_S

PI1

_C

SN

RF

_S

PI_

CS

N

RF

_S

PI_

SC

LK

RF

_S

PI_

MIS

OR

F_

SP

I_M

OS

I

TARGET_3V3

10RR65

AVCC

EZFET_TA RGET_UART_RXD

EZFET_TA RGET_UART_TXD

BR

IDG

E_T

AR

GE

T_

RE

AD

Y_O

UT

BR

IDG

E_T

AR

GE

T_R

EA

DY

_IN

1 2

3 4

5 6

7 8

9 10

11 12

13 14

15 16

PORT_9/ESI

MHDR2X8

TARGET_GND

TARGET_3V3

ESIVCCESICIESICI2ESICI0ESICH2/ESITEST2ESICH0/ESITEST0ESITEST4

TARGET_GNDESIVSSESICOMESICI3ESICI1ESICH3/ESITEST3ESICH1/ESITEST1

1 2

3 4

5 6

7 8

9 10

11 12

13 14

15 16

ESI

MHDR2X8

TARGET_GND

TARGET_3V3

ESIVCCESICIESICI2ESICI0ESICH2/ESITEST2ESICH0/ESITEST0ESITEST4

TARGET_GNDESIVSSESICOMESICI3ESICI1ESICH3/ESITEST3ESICH1/ESITEST1

12

34

56

78

PORT_1_4

MHDR2X4

12

34

56

78

PORT_2_3

MHDR2X4

12

34

56

78

PORT_6_8

MHDR2X4

12

34

56

78

PORT_J

MHDR2X4

1 2

3 4

5 6

7 8

9 10

11 12

13 14

15 16

17 18

19 20

RF2

MHDR2X10

1 2

3 4

5 6

7 8

9 10

11 12

13 14

15 16

17 18

19 20

RF1

MHDR2X10

0.1uFC32

TARGET_GND

0RR440RR450RR46

0RR47

TARGET_GND

0RR480RR490RR500RR51

TARGET_GND

0RR570RR560RR550RR54

0RR530RR52

TARGET_3V3

RF_SPI1_CSNRF_GPIO_82RF_SPI1_MISO/RF_UART_TXDRF_SPI1_MOSI/RF_UART_RXD


RF_SPI_CSNRF_SPI_SCLKRF_SPI_MOSIRF_SPI_MISO

RF_RESETRF_GPIO_81RF_GPIO_10

RF_SPI1_SCLK

LF

XO

UT

LF

XIN

HF

XO

UT

HF

XIN

PJ.0

PJ.1

PJ.1LED1LED2LFXINLFXOUTHFXINHFXOUTP6.0

P6.1P6.2

P6.0P6.1P6.2

RF_RESET RF_GPIO_81RF_GPIO_10 RF_GPIO_82

RF_SPI1_MOSI/RF_UART_RXDRF_SPI1_MISO/RF_UART_TXDRF_SPI1_SCLKRF_SPI1_CSN

RF_SPI_CSNRF_SPI_SCLKRF_SPI_MISORF_SPI_MOSI


I2C_SDAI2C_SCLUART0_RXD UART0_TXD

P4.3P1.7

P1.0P1.1

P1.6P4.2

P2.0P2.1P2.2P2.3P3.4

P3.5 P3.6P3.7

P6.0P6.1P6.2P8.4P8.5P8.6P8.7

PJ.0PJ.1PJ.2PJ.3PJ.4PJ.5PJ.6PJ.7

EZFET_TA RGET_TEST_SBWTCK

EZFET_TA RGET_RST_SBWTDIO

BR

IDG

E_T

AR

GE

T_U

AR

T_R

XD

BR

IDG

E_T

AR

GE

T_U

AR

T_T

XD

0.1uF

C36

TARGET_GND

COM1

COM2

Up3

Down4

Select5

Right6

Left7

BUT

TARGET_GND

BUT_AIN

BUT_AIN2

BUT_AIN3

BUT_AIN4

BUT_AIN5

BUT_AIN2

BUT_AIN3

BUT_AIN4

BUT_AIN5 TARGET_GND

TARGET_GND TARGET_GND

DNP

R41

DNP

R40

TARGET_3V3

TARGET_3V3






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Figure 29. Schematic, Sensor Board

http://www.ti.com






Figure 30. Schematic, Motor Board

http://www.ti.com


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