On Sat, 16 Aug 2014, Justin Richards wrote:

> Not exactly 100% sure what that does but it eliminates the errors.
>
> Thanks
>
> Now lastly the re-assembled file is 2 bytes larger than the original 4096
> as compared with 4098.  It needs to fit into a 4K EPROM.

I think what you are seeing here is that the disassembler if generating=20
Z80 style mnemonics for 8080 op codes, then the assembler is converting=20
the Z80 mnemonic into Z80 op codes.

e.g.

8080: RLA =3D 0x17
Z80:  RL A =3D 0xCB 0x17

"RL A" and "RLA" both do exactly the same thing except "0x17" takes 4=20
cycles to execute and "0xCB 0x17" takes 8

A good assembler will generate the faster 8080 version of a machine code=20
instruction in preference to the slower Z80 version if one exists.

I would suggest you try different assemblers to see if one will quickly=20
overcome your problem without any fiddling on your part.

BTW a useful book is the "Z80 instruction handbook" ISBN 0-8104-6275-3

The moral is: just as with compilers, some assemblers are MUCH better than=
=20
others.

Regards
Sergio Masci
--=20
http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist
.