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Timbucus · 1st Jul 2020, 6:54 pm

They are just copies that are the first thing SCiOS does when it goes in at START 0x22 (V2) that is the address in P3 when you do the XPPC P3 to go back - so if you have damaged it just set it but, becomes SCIOS version dependent.

They then get restored as is when it goes back out - so the last part of your picture is in P1,P2,A,E and S (for the bits that are reversible obviously) as you say the only one with a risk is the last one the Status register which will affect the Flags when SCIOS does the CAS - you would just need a small wrapper if you needed to use SCIOS which handled it setting the correct flags - not the end of the world - I.e. just set the last two bytes in your code to what you want in the picture and a sensible value as the last byte loaded for the flags...

1st Jul 2020, 6:54 pm	#103
Timbucus Octode Join Date: Mar 2019 Location: Barry, Vale of Glamorgan, Wales, UK. Posts: 1,364	Re: Mk14 vdu They are just copies that are the first thing SCiOS does when it goes in at START 0x22 (V2) that is the address in P3 when you do the XPPC P3 to go back - so if you have damaged it just set it but, becomes SCIOS version dependent. They then get restored as is when it goes back out - so the last part of your picture is in P1,P2,A,E and S (for the bits that are reversible obviously) as you say the only one with a risk is the last one the Status register which will affect the Flags when SCIOS does the CAS - you would just need a small wrapper if you needed to use SCIOS which handled it setting the correct flags - not the end of the world - I.e. just set the last two bytes in your code to what you want in the picture and a sensible value as the last byte loaded for the flags...