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1. Tim Ward ⭐🇪🇺🔶 #FBPE (timwardcam@c.im)'s status on Thursday, 02-Nov-2023 00:01:03 UTC Tim Ward ⭐🇪🇺🔶 #FBPE

   in reply to

   • F4GRX Sébastien
   • David Jones

   @f4grx @drj It was then, but I have a vague feeling that the 68010 or 20 allowed odd addresses. At a performance cost.

   • F4GRX Sébastien (f4grx@chaos.social)'s status on Thursday, 02-Nov-2023 00:01:05 UTC F4GRX Sébastien

     in reply to

     • David Jones

     @TimWardCam @drj I am not sure any 68k supports unaligned word acesses. that is probably an address error exception.

   • Tim Ward ⭐🇪🇺🔶 #FBPE (timwardcam@c.im)'s status on Thursday, 02-Nov-2023 00:01:06 UTC Tim Ward ⭐🇪🇺🔶 #FBPE

     in reply to

     • David Jones

     @drj It's an awful long time ago that I wrote any 68000 assembler - this was during the development of the QL which actually used a 68008.

     One booby trap I seem to recall was to do with moving more than one byte at a time via an A register used as a pointer and containing an odd number. Didn't work at all, but I have a vague feeling that this got "fixed" (at the cost of additional bus cycles) in later processors?

   • David Jones (drj@typo.social)'s status on Thursday, 02-Nov-2023 00:01:10 UTC David Jones

     Welcome to #MOVember, one asm MOV instruction each day.

     The Motorola MC68000 has a BEAST of a MOV instruction.
     Official assembler mnemonic: MOVE. Refreshingly clear!

     You could move to and from registers and/or memory. 8-, 16-, 32- data sizes. Post increment, predecrement. Including memory-to-memory moves (*Ferris Bueller soundtrack voice*: Oh Yeah).

     `*d++ = *s++` is a single instruction in 68000.

     Officially destination on the right: MOVE A7,D0 copies the A7 register to D0

     Please 🔁

     #68k