-
Between interrupts and handlersSee there's this short period of time immediately after an interrupt comes but [i]before[/i] the control is transferred to an interrupt handler, abou…
... can be delayed by several Tstates, so is the interrupt handler ... , making the INT pulse 32 Tstates in width (does any non ... exactly a certain number of Tstates from the moment the ULA ... -
Machine Code Routine of the weekHow about a thread that has a routine each week that is in [B]assembly language[/B] and is also described in great detail what the hell is going on …
... saving of 37,888 tstates and that is before ... would save another 92 tstates per char a further ... 47,104 tstates over 512 chars, so ... in total saving 84,992 tstates over 512 chars ;)
... PRMTX defb 17 ; saving 10 tstates
ATTCC defw $5800; ... -
Newbie willing to try doing some gfx...I've tried my wings in creating some hires graphics on C64 and I'd like to try making some also with speccy just out of curiosity, but my knowledge a…
... DOES NOT MEAN 625 lines 50hz video.
[QUOTE=Romppainen ... -
Spectrum Emulator that supports low resolutions and runs smoothlyHello to All, I have been trying to find a spectrum emulator that will work well through my CRT TV (using RGB to Scart) Most emulators seem to supp…
... released in Europe = 320x240 PAL 50Hz
= Black borders top and ... released in Europe 320x240 PAL 50Hz
= Black borders top and ... on CRT
320x240 50hz does not
320x240 ... is designed for a PAL 50Hz display
don't ... -
Spectrum Emulator that supports low resolutions and runs smoothlyHello to All, I have been trying to find a spectrum emulator that will work well through my CRT TV (using RGB to Scart) Most emulators seem to supp…
... has borders when run in 50hz, spectrum never ran in 320x240 ... -
Spectrum Emulator that supports low resolutions and runs smoothlyHello to All, I have been trying to find a spectrum emulator that will work well through my CRT TV (using RGB to Scart) Most emulators seem to supp…
... has borders when run in 50hz, spectrum never ran in 320x240 ... -
Spectrum Emulator that supports low resolutions and runs smoothlyHello to All, I have been trying to find a spectrum emulator that will work well through my CRT TV (using RGB to Scart) Most emulators seem to supp…
... card in the Wii does 50Hz PAL composite video out. Not ... -
Multiply the value of 'a' by 5Is there a way of multiplying the value of 'a' by 5? I've tried 'add a,a' etc. but only get multiples of 2...
You could use RLA, which only takes 4-tstates, instead of SLA A if you're sure that it won't carry.
If it does carry, you'd have to do something other than just ADD A,A in any case. -
Zymosis -- WTFPL'ed Z80 Emulation Corebreaking news! i'm back with another useless project: new Z80 emulation core written in pure C! i hear you screaming: "oh, no! WHY?!" let me tell yo…
... SideWize working without strange '+6 tstates' i added to make it ... -
Zymosis -- WTFPL'ed Z80 Emulation Corebreaking news! i'm back with another useless project: new Z80 emulation core written in pure C! i hear you screaming: "oh, no! WHY?!" let me tell yo…
... SideWize working without strange '+6 tstates' i added to make it ... -
T-States?Can anyone point me to any good reading (or summarise) that will explain exactly what a tstate is? At the moment for me, tstates are a useful gauge …
... -Tape;641343]
So, why tstates and what are they please ... -
64x48 full colour graphicsHow feasible is this? Could an interrupt-driven routine be used to, for example, fill the top two thirds with a 64x32 blocky picture and leave the bo…
... ;11
takes 21 tstates = 10,5 tstate for one ... =32 bytes would need 336 tstates.
One line is ... drawn by ULA in 224 tstates. But me may start coping ... it give us about 400 tstates to do the job? -
64x48 full colour graphicsHow feasible is this? Could an interrupt-driven routine be used to, for example, fill the top two thirds with a 64x32 blocky picture and leave the bo…
I wonder if we could ignore the stack and do:
LD (HL),N
INC L
It's 14 tstates, slower than PUSH but faster than LDI and goes in the same direction as raster -
64x48 full colour graphicsHow feasible is this? Could an interrupt-driven routine be used to, for example, fill the top two thirds with a 64x32 blocky picture and leave the bo…
... desperately to get some more tstates.
I'll work ... -
64x48 full colour graphicsHow feasible is this? Could an interrupt-driven routine be used to, for example, fill the top two thirds with a 64x32 blocky picture and leave the bo…
... -10+7+10+7 =34 tstates. At the beginning I was ... is just 10+16=26 tstates. Much better.
I ... -
64x48 full colour graphicsHow feasible is this? Could an interrupt-driven routine be used to, for example, fill the top two thirds with a 64x32 blocky picture and leave the bo…
...
;; Top border ~ 14366 tstates
;; Is there a cleaner ... -
[NEW] Speccy for Android ReleasedHello, All! A while ago, I have released the Android version of [i]Speccy[/i], my ZX Spectrum emulator. It emulates Spectrum 16k, 48k, 128k, +2, +2A…
... rate is fully synchronized with 50Hz spectrum screen and result is ... -
Zymosis -- WTFPL'ed Z80 Emulation Corebreaking news! i'm back with another useless project: new Z80 emulation core written in pure C! i hear you screaming: "oh, no! WHY?!" let me tell yo…
... code somehow to use the tstates and next_event_tstate fields of the ... -
Zymosis -- WTFPL'ed Z80 Emulation Corebreaking news! i'm back with another useless project: new Z80 emulation core written in pure C! i hear you screaming: "oh, no! WHY?!" let me tell yo…
[i]>[C++ Warning] zymosis.c(195): W8081 void functions may not return a value[/i]
yes, it's a typo. just delete 'return', it's really 'void'.
[i]>[C++ Warning] zymosis.c(968): W8008 Condition is always true[/i]
no, that ... -
Zymosis -- WTFPL'ed Z80 Emulation Corebreaking news! i'm back with another useless project: new Z80 emulation core written in pure C! i hear you screaming: "oh, no! WHY?!" let me tell yo…
... you must correct z80->tstates in portIn and portOut callbacks ... -
Zymosis -- WTFPL'ed Z80 Emulation Corebreaking news! i'm back with another useless project: new Z80 emulation core written in pure C! i hear you screaming: "oh, no! WHY?!" let me tell yo…
... ' callback and should not modify 'tstates' in port i/o callbacks ... -
Spectrum Emulator that supports low resolutions and runs smoothlyHello to All, I have been trying to find a spectrum emulator that will work well through my CRT TV (using RGB to Scart) Most emulators seem to supp…
... 312 line video signal at 50Hz and that 8 lines are ... -
The need of having a 257-byte table for IM2 routinesThis came from a discussion at the speccy.org forum. I have understood that the reason behind the 257-table for IM 2 routines is due to certain joys…
... to be run on the 50Hz interrupt (additional interrupts may make ... -
Performance Analyser?Disclaimer: Im asking this question as a "non-programmer" so please forgive my ignorance if this turns out to be a daft question. During the life-sp…
... as I could on a 50Hz counter to the original pacman ... -
Work out attribute location in MCHow do I go about writing a MC routine which calculates the attribute address from a set of PRINT co-ordinates. I know you in basic you multiply the…
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It could be 4 tstates faster if you have room ... -
SPECTRA New from Paul FarrowLooks good! Read about it [URL="http://www.fruitcake.plus.com/Sinclair/Spectrum/Spectra/SpectraInterface.htm"]here[/URL]
... using that clock and the 50Hz INT signal would be enought ... -
SPECTRA New from Paul FarrowLooks good! Read about it [URL="http://www.fruitcake.plus.com/Sinclair/Spectrum/Spectra/SpectraInterface.htm"]here[/URL]
... a visual distinction between the 50Hz (PAL) rendering of the two ...