Summary of Hardware Connections

ECG Module (ADS1293)

ECG front end (ADS1293) is connected to the microcontroller (CC2541)

through SPI interface which includes Serial Data In, Serial Data Out and Serial

Clock. Other collections like chip select, Interrupts etc. are explained in the

following points.

Chip Select of the front end, which is an active low signal is connected to the

P1.1 of microcontroller.

DRDYB Pin of the front end, which is an active low signal is connected to the

P1.6 of microcontroller.

ALARMB Pin of the front end, which is an error status signal is connected to the

P0.6 of microcontroller.

WCT, RLD and CMOUT are brought out on the input berg strip.

Reset pin of the front end is directly pulled high.

A 4.096 MHz Crystal (high frequency) and 32.768 kHz Crystal (low frequency) is

used to clock the Front End.

Rest of the interrupt signals of the Front End are kept floating, because those

signals are redundant and also no port pins available on microcontroller.

Battery charging unit (BC24010)

Independent charging unit for Li-Ion battery(BL-5C / 3.7V).

Output of the battery is connected to the ADC channel P0.0 of the

microcontroller via voltage divider network (2:1) to measure the battery level.

Accelerometer (LIS331)

Accelerometer (LIS331) is connected to the microcontroller through SPI

interface which includes Serial Data In, Serial Data Out and Serial Clock.

Other collections like chip select, Interrupts etc. are explained in the following

points.

Chip Select Pin of Accelerometer, which is an active low signal is connected to

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the P1.0 of microcontroller.

INT1 Pin of the Accelerometer, which is an interrupt signal is connected to the

P0.7 of microcontroller.

Rest of the interrupt signals of the Accelerometer are kept floating, because those

signals are redundant and also no port pins available on microcontroller.

UART to USB Bridge (FT230)

It is an UART to USB Bridge which is connected to the controller through Rx,

Tx, CTS and RTS pin.

USB interface is used for data transfer from SD card and battery charging via

USB port.

No other interface with the controller.

Temperature (ADT7301)

Temperature measuring unit (ADT7301) is connected to the microcontroller

through SPI interface which includes Serial Data In, Serial Data Out and Serial

Clock.

Chip Select Pin of Temprature Measuring unit, which is an active low signal is

connected to the P0.1 of microcontroller.

SD Card

SD Card is connected to the microcontroller through SPI interface which includes

Serial Data In, Serial Data Out and Serial Clock.

Chip Select Pin of the SD Card, which is an active low signal is connected to the

P1.7 of microcontroller.

SpO2 Module (AFE4490)

SpO2 front end (AFE4490) is connected to the microcontroller (CC2541 on

other board) through SPI interface which includes Serial Data In, Serial Data

Out and Serial Clock. Other collections like chip select, Interrupts etc. are

explained in the following points.

Chip Select and AFE_~PDN of the front end, which are active low signals is

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connected to the P2.0 of microcontroller through a 1:2 Decoder (When chip

select is low AFE_~PDN is high and Vice-Versa).

DIAG_END Pin of the front end, which is an active high signal is connected to

the P0.4 of microcontroller (on the other board).

Reset pin of the front end is directly pulled high.

An 8 MHz Crystal is used to clock the Front End.

Rest of the interrupt signals of the Front End are kept floating, because those

signals are redundant and also no port pins available on microcontroller.

CC2541

A custom made 5 pin JTAG is there on board to program microcontroller.

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