Lab. 1 – Task 1 to 4 details

For more details – see the Lab. 1 web-site

There will be a 20 min prelab-quiz (based on Assignment 1 and 2) at the start of the lab. session

You can make use of YOUR class notes during the prelab-quiz. You CAN’T access the web or use your partner’s notes

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Laboratory 1 – Tasks 1 to 4 in detail

1. Download the C++ Talk-through program. Check that you can hear the audio output

2. Convert the ProceessDataCPP( ) code into assembly code ProcessDataASM( )

Check that you can hear the audio output

3. Routine for initializing the PF lines (programmable flags)

Use the provided tests to check your code

4. Develop the ReadProgrammableFlagsASM( ) to read the switches

MUTE-BUTTON -- Develop code so that if switch 1 is pressed, the sound stops. If switch 1 is released, then the sound starts again.

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Set up for Tasks 1 and Task 2

AUDIO-IN

AUDIO-OUT

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Task 1Download audio-talk-through program If you have not already done so, download and expand

ENCM415Directory.zip file so that you have the correct directory. structure and test driven development environment needed for Laboratory 1.

Download and expand the files in CPP_Talkthrough.zip into your Lab1 directory.

Add the CPP_Talkthrough project in your Lab. 1  directory to the VisualDSP environment -- compile and link.

Download the executable (.dxe) file onto the BF533 processor.

Hook up your CD or IPOD output to the CJ2 stereo input. Hook up your ear-phones to the CJ3 stereo output. Run the CPP_Talkthrough.dxe executable and check that the talk

through program is working.

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Question What is a “talk-through program”?

Clear example of applying the first two rules of assembly language programming

Rule 1: If you have a choice – don’t use assembly code It takes as much time (and SOST) to “design, code,

review, test and maintain” one line of C++ code as it does assembly code, but one line of C++ often can do more

Rule 2: If somebody has a working example, cannibalize it for your own work (if legal)

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The talk through program (C++)Prepare to run C++ code

(before you get to main( ))

Set up the EBIUExternal Bus Unit

Use EBIUto initialize A/D and D/A

SET UP theA/D and D/A interrupts

while (1) {/* Wait for messages */ }

ACTIVATE the A/D and D/A interrupts

Every1 / 44,000 s

Store A/D register value(DMA) into memory

Call ProcessDataCPP( )or ProcessDataASM( )

Load memory (DMA) into D/A register

Set messages and flagsto main( )

main( ) ISR -- Interrupt Service Routine

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main( )

int main(void){

sysreg_write(reg_SYSCFG, 0x32); //Initialize System Configuration Register

Init_EBIU();Init_Flash();Init1836();Init_Sport0(); // Serial PORTInit_DMA();Init_Sport_Interrupts();Enable_DMA_Sport0(); // Serial PORT

while (1) { /* */ }}

Prepare to run C++ code(before you get to main( ))

Set up the EBIUExternal Bus Unit

Use EBIUto initialize A/D and D/A

SET UP theA/D and D/A interrupts

while (1) {/* Wait for messages */ }

ACTIVATE the A/D and D/A interrupts

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ProcessDataCPP( )

#include "Talkthrough.h"

extern volatile int iChannel0LeftIn, iChannel0LeftOut;void Process_DataCPP(void){

iChannel0LeftOut = iChannel0LeftIn;iChannel0RightOut = iChannel0RightIn;iChannel1LeftOut = iChannel1LeftIn;iChannel1RightOut = iChannel1RightIn;

}

TASK 1 – Download the Talkthrough program and check that it works

Need an audio in signal (Ipod, CD player)Need ear-phones to check output signal

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Task 2 -- ProcessDataASM( )

extern volatile int iChannel0LeftIn, ………….; // #include "Talkthrough.h"

// void Process_DataASM(void)// {// iChannel0LeftOut = iChannel0LeftIn;// iChannel0RightOut = iChannel0RightIn;// iChannel1LeftOut = iChannel1LeftIn;// iChannel1RightOut = iChannel1RightIn;// }

TASK 2 – Replace ProcessDataCPP( ) by ProcessDataASM( ) and check that it works

This is essentially Q2 from assignment 2

Need an audio in signal (Ipod, CD player)Need ear-phones to check output signal

.extern _iChannel0LeftIn;

.section program

.global _Process_DataASM__Fv;

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Task 2 -- Convert ProcessDataCPP( ) to ProcessDataASM () – Assign. 2 Q2 In talkthrough.h. add a prototype for your assembly code function

Process_DataASM;

In ISR.cpp change to

// call function that contains user code#if 0      Process_DataCPP();  // Use the C++ version#else     Process_DataASM(); // C assembly code routines especially developed for Lab. 1#endif 

Right-click on ProcessDataCPP.cpp entry. Use "FILE OPTIONS“ to exclude linking

Use PROJECT | clean project Add your ProcessDataASM.asm file to the project, recompile and link.

Check that your code works More details on the Lab. 1 web pages

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Things to remember

Both MIPS and Blackfin are “RISC” type of processors

They have a “LOAD / STORE” architecture

iChannel0LeftOut = iChannel0LeftIn;

BECOMES

Set P0 to point to address iChannel0LeftInMove memory value into register R0 = [P0]; LOAD

Set P1 to point to address iChannel0OutMove register value into memory [P1] = R0; STORE

REMEMBER – addresses and int, unsigned int values together withlong int, unsigned long int values are 32-bits on this processor

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How we are building the volume controller

SWITCHES ON FRONT PANEL

PROGRAMMABLE FLAGS

FIO_FLAG_D Register

YOUR PROGRAM RUNNING ON THE BLACKFIN

LED LIGHTS ON FRONT PANEL

LED-CONTROLREGISTER

EBIU INTERFACE

ProcessDataASM( ) subroutine

A/D D/A Interrupt routine D/AEAR

PHONESA/D

IPODCD

int ReadSwitches( ) void WriteLED(int )

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Set-up for Tasks 3 and 4

1. De-activate Visual DSP2. Power down Blackfin3. Connect power to “special Blackfin interface”

connector4. Connect 50-pin cable to logic-lab5. Connect 50-pin cable to Blackfin6. Power up logic lab. station7. Power up Blackfin8. Reactivate Visual DSP9. Check that station works using “Lab. 1 test-executable”

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Special “power-connector” for Blackfin interface on logic lab. station

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Special “power-connector” for Blackfin interface on logic lab. station

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Connect 50-pin cable to Blackfin

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Connect 50-pin cable to logic lab

Make sure that all 50-pin connections are secure and proper.

Power up the logic lab. station and check that is working

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Task 3 – Initialize the Programmable flag interface – 16 I/O lines on the Blackfin

Warning – could burn out the Blackfin processor if done incorrectly

You need to set (store a known value to) a number of Blackfin internal registers

Most important ones FIO_DIR – Data DIRection – 0 for input **** FIO_INEN – INterface ENable – 1 for enabled FIO_FLAG_D – Programmable FLAG Data register

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Why do you need to know how to do read (load) and write (store) on internal registers?

Flag Direction register (FIO_DIR) Used to determine if the PF bit is to be used for input or

output -- WARNING SMOKE POSSIBLE ISSUE Need to set pins PF11 to PF8 for input, leave all other pins

unchanged

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Write the Blackfin assembly language instruction(s) to load the address of the internal programmable flag FIO_DIR register into pointer register P1 – then set the Blackfin PF lines to act as inputs

#include <defsBF533.h>

#include <macros.h>

P1.L = lo (FIO_DIR);

P1.H = hi (FIO_DIR);

// Check the requirements – need to have all input

// Manual says “setting a line for input means setting bit values to 0”

R0 = 0;

W[P1] = R0;

ssync; // Force Blackfin to do the write (store) NOW not later

Making sure that the FIO_DIR is correct for LAB. 1 – NOTE may need to change for later labaoratories

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Registers used to control PF pins

Flag Input Enable Register Only activate the pins you want to use (saves power in

telecommunications situation) Need to activate pins PF11 to PF8 for input, leave all other pins

unchanged

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Registers used to control PF pins

Flag Data register (FIO_FLAG_D) Used to read the PF bits (1 or 0) Need to read pins PF11 to PF8, ignore all other pins values

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Task 3 – Setting up the programmable flag interface Follow the instructions carefully FIO_DIR – direction register – write 0’s to all bits

In later laboratories will be writing 1’s to some bits and writing 0’s to other bits – DO IT RIGHT

FIO_INEN – input enable register – write 1’s to bits 8, 9, 10, 11

Other registers set to 0

There is a test program (Weds lecture) that will enable you to check your code – provide a screen dump of the test result to show it works Use PRT-SCR button and then paste in .doc file.

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Task 4 – Read the switches on the front pannel Final laboratory requirements

SW1 connected to PF8 -- Mute button (This task) SW2 connected to PF9 -- Gargle button (Task 5) SW3 connected to PF10 -- Volume up (Task 7) SW4 connected to PF11 -- Volume down (Task 7)

Build Initialize_ProgrammableFlagsASM ( ) Modify main( ) and ProcessDataASM( ) so that MUTE-operation

works MUST HAVE 50 pin cable connected between logic board and

Blackfin Logic board power supply must be turned on

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#include <defsBF533.h>

#include <macros.h>

.global _ReadProgrammableFlags__Fv;

_ReadProgrammableFlags__Fv

LINK 16;

P1.L = lo (FIO_FLAG_D); // could be P0

P1.H = hi (FIO_FLAG_D);

R0 = W[P1] (Z);

P0 = [FP + 4];

UNLINK;

_ReadProgrammableFlags__Fv; JUMP (P0);

Must use W [ ]since the manual shows that FIO_FLAG_D register is 16-bits

Must use W[P1] (Z) zero-extend as this adds 16 zeros to the 16 bits from FIO_FLAG_D register to make 32-bits to place into R0

int ReadProgrammableFlags( )

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How to use int ReadProgrammableFlags( )

int switch_setting = ReadProgrammableFlags( );

SWITCHES ON FRONT PANEL

PROGRAMMABLE FLAGS

FIO_FLAG_D Register

int ReadSwitches( )

(FIO_POLAR register = 0)

All switches unpressed

Binary Pattern in FIO_FLAG_D register

B????0000????????

All switches pressed

Binary Pattern in FIO_FLAG_D registerB????1111????????

Binary ? Means – we don’t know what the answer is

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How to use int ReadProgrammableFlags( )

int switch_setting = ReadProgrammableFlags( );

SWITCHES ON FRONT PANEL

PROGRAMMABLE FLAGS

FIO_FLAG_D Register

int ReadSwitches( )

(FIO_POLAR register = 0)

All switches unpressed

Binary Pattern in FIO_FLAG_D register

BXXXX0000XXXXXXXX

All switches pressed

Binary Pattern in FIO_FLAG_D registerBXXXX1111XXXXXXXX

Binary X Means – we don’t know what the answer is – and don’t care

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Echoing the switches to the LEDCode in main( ) – written in C++int main( ) {

InitializeSwitchInterface( ); // Check Lab. 1 for “exact name needed”InitializeLEDInterface( );

#define SWITCHBITS 0x0F00 // Looking in MIPs notes about // using a mask and the // AND bit-wise operation

// to select “desired bits” while (1) { // Forever loop int switch_value = ReadProgrammableFlagsASM( );

int desired_bits = switch_value & SWITCHBITS;

int LED_light_values = desired_bits >> 8; // Bits in wrong position

WriteLEDLights(LED_light_values);

}

}

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Practice example -- Rewrite the code so that loop stops if all the switches are pressed at the same time

int main( ) {

InitializeSwitchInterface( ); // Check Lab. 1 for “exact name needed”InitializeLEDInterface( );

#define SWITCHBITS 0x0F00 // Looking in MIPs notes about MASKS

while (1) { // Forever loop int switch_value = ReadProgrammableFlagsASM( );

int desired_bits = switch_value & SWITCHBITS;

int LED_light_values = desired_bits >> 8; // Bits in wrong position

WriteLEDLights(LED_light_values);

}

}

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Practice example 2 -- Rewrite the code so that (1) loop stops if all the switches are pressed at the same time and (2) if SW1 is pressed then the volatile int mute_on variable is set to 1, otherwise it is set to 0(3) Always show (in the lights) the last value of the switches

int main( ) {

InitializeSwitchInterface( ); // Check Lab. 1 for “exact name needed”InitializeLEDInterface( );

#define SWITCHBITS 0x0F00 // Looking in MIPs notes about MASKS

while (1) { // Forever loop int switch_value = ReadProgrammableFlagsASM( );

int desired_bits = switch_value & SWITCHBITS;

int LED_light_values = desired_bits >> 8; // Bits in wrong position

WriteLEDLights(LED_light_values);

}

}

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Laboratory 1 – Tasks 1 to 4 in detail

1. Download the C++ Talk-through program. Check that you can hear the audio output

2. Convert the ProceessDataCPP( ) code into assembly code ProcessDataASM( )

Check that you can hear the audio output

3. Routine for initializing the PF lines (programmable flags)

Use the provided tests to check your code

4. Develop the ReadProgrammableFlagsASM( ) to read the switches

MUTE-BUTTON -- Develop code so that if switch 1 is pressed, the sound stops. If switch 1 is released, then the sound starts again.