Sorry for the delay.
- in PAL mode: 1 frame ~= 312 scanline (312*207TS -> 19.872 msec ~50,322Hz)
in NTSC mode: 1 frame ~= 262 scanline (262*207TS -> 16.687 msec ~59,925Hz)
It seems that there is a reserve in PAL mode (<20 msec), therefore the length of the frame can be extended.
In the revised version 314 scanline forms a frame: 314*207TS -> 19.999 ms ~ 50.002 Hz.
this may cause the flickering display - I rebuilt the program w.312 scanline - try it, pls.
- Which Speccy file type is equivalent to a ZX81 P-file?
-> as drBeep wrote the TAP
- And where (at which address) do I have to load it?
-> SysVAR PROG
(23635=$5C53) points to startaddress
- Do I have to update afterwards some system variables?
-> Yes, more (e.g. NEWPPC,E PPC,VARS,E LINE,X PTR,WORKSP)
- Which address range has to be written to MMC to save a complete program?
- check it in ROM-code (IX points to a header-block) - perhaps easier to use the ROM routines
- -> from addr. pointed by sysvar PROG to addr. (pointed by E_LINE) -1
- How do I switch form SLOW to FAST mode and back
- in BASIC: REM =>fast and REM =>slow - where "=>" is SHIFT+Y
in asm: SW_FAST = call $054c and SW_SLOW = call $1296
SPONZY's RAM check is same as the Speccy's - the above
can be a good solution "to 'protect' the upper 32K"
drBeep is right, no reserved registers in SPONZY
ps: I will publish the source code with comments as well, as soon as possible. (few months )
EDIT: the attachment was removed. Here is the final version of SPONZY
Last edited by zsolt
on Mon May 28, 2012 9:03 pm, edited 1 time in total.
ZX81 (8K), ENTERPRISE 128, [ZX SPECTRUM (48K,+,+128K,+2,+2A), TS1000, TS1500, TS2068, Cambridge Z88, PRIMO A64 (red)]