Source/Destination values In Assembly Instructions

kicchip — Thu, 28 Jan 2010 11:38:15 GMT

Hi,

Looking at different device families...

With AVR I'd use:

<SomeInstruction> Destination , Source

MOV r0,r1 ; move r1 into r0

With PIC I'd use:

<SomeInstruction> Source , Destination

MOV w0 , w1 ; move w0 into w1

For Freescale I'd use:

<SomeInstruction> Source , Destination

I prefer "thinking" Source,Destination because it looks like stuff is moving from left to right so it's more intuitive (to me at least), and this is how I'd like to build my macros and explain to students.

But I'm not familiar with all freescale products, and products from other manufacturers, so would people agree that the Source,Destination is the most widely supported "way" at least for freescale products, do people know about other assembly languages that are popular that use the opposite way??

Any help, ideas thoughts welcome...Thanks

Re: Source/Destination values In Assembly Instructions

bigmac — Thu, 28 Jan 2010 21:30:03 GMT

Hello,

I am not familiar with all the Freescale products either.

But perhaps the original "thinking" might have been somewhat connected to the endianness of each product. The Freescale product is big endian, whereas the AVR product appears to be little endian, where the address byte sequence is "reversed".

I seem to recall that the Intel CPUs were similar to the AVR, but I am not entirely certain.

Regards,

Mac

topic Source/Destination values In Assembly Instructions in 8-bit Microcontrollers

Source/Destination values In Assembly Instructions

Re: Source/Destination values In Assembly Instructions