Hello again, it has been far too long since I’ve updated this blog. They say excuses are like assholes–they’re full of shit. So I won’t give any and just jump right in…
I am learning assembly programming on the MSP430 from Texas Instruments. After a failed attempt at learning x86 assembly, I was recommended the MSP430 and so far it seems like the right choice.
The MSP430 is a 16 bit low power microcontroller. It has a von Neumann architecture which means that there is only one address space for program code and memory. It is also a RISC system or more accurately a RISC like system. There are only 27 core instructions in its instruction set but, unlike pure RISC systems, it can do arithmetic on values directly in main memory.
The MSP430 is also cheap. I am using an MSP430 Launchpad that costs less than five dollars. The Launchpad is a complete development board that includes an onboard debugger/emulator. On the software side of things, I am using the free Kickstart version of the IAR Embedded Workbench IDE for the MSP430. There are no code size restriction for the assembler. Finally, I am using a book titled MSP430 Microcontroller Basics by John H. Davies. This book was also highly recommended.
Here’s my first assembly program. It’s from the book but slighty modified because the book uses a different development kit. It turns on LED2 on the Launchpad.
1 2 3 4 5 6 7 8 9 10 11 12 13 | #include <msp430g2553.h>
RSEG CODE
Reset:
mov.w #WDTPW|WDTHOLD,&WDTCTL ; Stop watchdog timer
mov.b #01000000b,&P1OUT ; Turn on P1's 6th bit
mov.b #01000000b,&P1DIR ; Set P1OUT.6 to output
InfLoop:
jmp InfLoop ; Infinite loop
;-----------------------------------------------------------------------
RSEG RESET ; Reset vector segment
DW Reset ; Address to start
END |
The surfuace mount 32kHz crystal included in the MSP430 Launchpad box.
Pads for the crystal.
Crystal soldered! It wasn’t too bad.