Need Some Help In 68K microprocessor

[Jamjoom(EE)]

Hello Everyone, I'm taking a course in microprocesors and i need to know the basic concept of Data and Adress Registers as weel as the differences between some of the language operations of the microprocessor's like Move.B and Move.L and Add.B etc...

 

[UTMonkey]

Hi,

Its been a while since I last looked at the 68000, it does have quite a feature rich instruction set.

So rich in fact that you could do with getting a book on the subject or find some resources on the net.

www.cse.wustl.edu/~jwhite/class/coe455/proglab.pdf
Easy Motorola 68k Reference


the 68000 has 8 32bit Data registers (or variables if you like to think of them that way) D0 - D7 and 8 32bit Address registers (or pointers) A0-A7.

please note A7 is used as the stack so in effect you only have 7, but it is plenty!

the .B .W .L extension basically instruct the process of the data width to work with.

for example:-
move.b D0,(A0)+

This moves the BYTE (first 8 bits) of data held in D0 into the address pointed to by A0, the + at the end increments the value in A0 by one byte.

Good luck!

Mark

p.s. I believe the example demonstrates "Indirect byte transfer with post increment!"