Embedded Programming

Hi pals?..this is the embedded programming week and its sort of a recap of last week Electronics Design where I redrew the Hello world board adding an led and a button which was a success...only this time I`m being required to program the board to do something in as many programming languages as possible.. I took up the challenge with great zest since I was trying to catch up in electronics quite fast...
Let me start by pointing out a few key areas Prof. Neil touched upon..

various architectures i.e Harvard, von Neumann RISC, CISC microprocessor, microcontroller FPGA, CPLD ALA

Several peripherals such as: A/D ,comparator, D/A, timer/counter/PWM,USART, USB,,

programmer families we introduced:8051 PIC MSP AVR ARM STM32 PSoC, xCORE, Propeller

Various AVR processors were explained in detail:

ATtiny10 ATtiny45V ATtiny44A ATmega328P ATmega16U2 ATxmega16E5 ATxmega16C4
Wait a minute::

Ok this are the design as designed and modified in Eagle CAD:
_________...
This is me working on the board accompanied with the final working board..
_________...
Not so fast pals.. here is the code I used in making the board work...The first programming language I worked with was C and used AVR to generate makefile...I used an off-the shelf programmer not FabIsp..
.include "tn44def.inc"
.equ ledpin = PB2; led pin
.equ led_port = PORTB; led port
.equ led_dir = DDRB; led direction
.equ delay_value=255 ; delay time in cycles

.def temp = R17; temporary storage
.def temp1 = R18; temporary storage
.def temp2 = R19; temporary storage
.def temp3 = R20; temporary storage

.cseg
.org 0; boot
rjmp reset



delay:
mov r16,temp
outer_loop:; duration ~

ldi r26, 0; set r26 to zero
ldi r27, 0; set r27 to zero
delay_loop:;~262143*65535+3= 17179541508 cycles
adiw r26, 1; add 1 to r26 and r27
ldi r28, 0; set r28 to zero
ldi r29, 0; set r29 to zero
delay_loop1:;~4*65535+3= 262143 cycles
adiw r28, 1; add 1 to r28 and r29; 2 cycles
brne delay_loop1; if no overflow loop; 1 or 2 cycles
brne delay_loop; if no overflow loop

dec r16; dcrement R16
brne outer_loop; if no overflow loop
ret


;
; main program
;
reset:
; designate fuse 0x7E for 20 MHz resonator
;
; designate clock divider to /1
;
ldi temp, (1 << CLKPCE)
ldi temp1, (0 << CLKPS3) | (0 << CLKPS2) | (0 << CLKPS1) | (0 << CLKPS0)
;ldi temp1, (1 << CLKPS3) | (0 << CLKPS2) | (0 << CLKPS1) | (0 << CLKPS0);/256
out CLKPR, temp
out CLKPR, temp1
;
ldi temp, high(RAMEND)
out SPH, temp
ldi temp, low(RAMEND)
out SPL, temp
;
; init led pin as input
;
;sbi = Set Bit in I/O Register
;
sbi led_port,ledpin
sbi led_dir,ledpin
;
; start main loop
;
loop:
sbi led_port,ledpin; led ON
ldi temp,100;delay 1 sec
rcall delai; delay
cbi led_port,ledpin; led OFF
ldi temp,50;delay 0.5sec
rcall delai; delay
rjmp loop; relative jump to loop

You can also check my first code I used but was quite an issue so i decided to move on with the above code...I'm just saying you could give it a try maybe it'll work....

#include
#include
#define bit_get(p,m) ((p) & (m))
#define bit_set(p,m) ((p) |= (m))
#define bit_clear(p,m) ((p) &= ~(m))
#define BIT(x) (0x01 << (x))
int main()
{
//SETUP
//Button is on PA3
//LED is PA7
bit_clear(DDRA,BIT(2)); //clear DDRA bit 7 makes PA3 (pin 6) an input to monitor my pushbutton - I don’t need pull-up resistor
bit_set(DDRB,BIT(5)); //Set DDRA bit 2 makes PA7 (pin 5) an output to control my LED
//LOOP
while (1)
{
if(bit_get(PINA,BIT(2)))//button is not
{
bit_clear(PORTB,BIT(5));//LED is off
}
else // button is pushed
{
bit_set(PORTB,BIT(5));//LED is on

}
}


Ok this is the rest of the material we covered in class:
packages :
DIP SOT SOIC TSSOP TQFP LQFP MLF, CSP, BGA

clocks : RC (10%, 1% calibrated) ceramic (0.5%) quartz (50 ppm)

in-system development :

ISP (header, pads, clip) bootloader JTAG, debugWire, PDI ICE

programmers :

ISP AVRISP FabISP avrdude JTAG, debugWIRE, PDI Atmel-ICE

assembly language : hex file instruction set, opcodes mnemonics, directives, expressions avr-as gavrasm C GCC AVR Libc

modules types math avr-libc, binutils-avr, gcc-avr WinAVR CrossPack Atmel Studio

host communication : RS232 bit timing VT100/ANSI/ISO/ECMA terminal Kermit Minicom term.py USB software

hardware FTDI cable libFTDI echo hello-world hello.ftdi.44.cad board components traces interior

programming hello.ftdi.44.echo.c hello.ftdi.44.echo.c.make hello.ftdi.44.echo.interrupt.c hello.ftdi.44.echo.interrupt.c.make

hello.ftdi.44.echo.asm hello.ftdi.44.echo.asm.make

IDE :

Atmel Studio Eclipse AVR Firefly Scratch Modkit

boards :
Arduino board + C libraries + IDE + bootloader Fabkit Fabio hello.arduino.328P.cad board components traces

interior Blink.pde boards.txt programming hello.arduino.328P.blink.c hello.arduino.328P.blink.make programming

ATtiny PSoC Maple Tessel BeagleBone PandaBoard Rasberry Pi

Interpreters :

Python BASIC FORTH AVRSH JavaScript

debugging :

"printf" Atmel Studio gdb, ddd, Insight

STM32:

processor STM32F3 data sheet toolchain gcc-arm-none-eabi sudo add-apt-repository ppa:terry.guo/gcc-arm-embedded

OpenOCD http://sourceforge.net/projects/openocd/files/latest/download?source=files QStlink2 sudo add-apt-repository ppa:mobyfab/qstlink2

stlink git clone https://github.com/texane/stlink.git programmer ST-Link V2 software ST library STMCube board

STM32F3Discovery software blink.zip programming Nucleo

Well thats it for this week, I`ll keep on practicig and updating however till next time..cheers.