[A83] Re: more unconventional instructions


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[A83] Re: more unconventional instructions




Suspected so about the SFC instruction.
Can be quite useful in routines.

 
> 
> Some of these are unconventional, others are not.
> 
> SLP OT0 IN0 OTDM OTDMR OTIM OTIM etc are Z180 instructions.
> 
> RETI is used to return from an interrupt. On calcs, it is equivalent to RET.
> RETN is used to reutrn from non-maskable interrupt. Not used on calcs.
> 
> OTIR, OTDR, OTI, OTD, INIR, INDR, INI, IND are used with ports. See Ch 13 of
> the Zilog docs for exact info. They're almost useless on calcs, although
> they can be quite useful to read the keyboard port:
>    ld bc,16
>    ld hl,masks
> loop:
>    oti
>    ini
>    jp pe,loop
> 
> masks:
>    .db mask,current_kb_state
>    .db mask,current_kb_state
>    ;...
> 
> SCF is not at all unconventional. It sets the carry flag.
> 
> -----Original Message-----
> From: assembly-83-bounce@lists.ticalc.org
> [mailto:assembly-83-bounce@lists.ticalc.org]On Behalf Of Hyperbyte
> Sent: Monday, July 02, 2001 8:02 AM
> To: assembly-83@lists.ticalc.org
> Subject: [A83] more unconventional instructions
> 
> 
> 
> I found a few more:
> 
> RETI
> 
> RETN
> 
> SLP (sleep?)
> 
> OTDM,OTDMR,OTDR
> 
> OTIM,OTIMR,OTIR
> 
> OUT0
> 
> OUTD
> 
> OUTI
> 
> SCF
> 
> 
> --thanks
> 
> 
> 




References: