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Small Machine Code Routines Which Maybe UsefulAs part of creating Flynn's Adventure in Bombland I created a lot of little routines to do all sorts of things. A lot of these I created based on inp…
Here's a T state delay routine, might come ...
; Usage: HL=delay, T states; HL > 123
Vega ARM SOC?I read that the core of the new Vega was an ARM SOC. I thought it would have been an FPGA. But it seems it's an ARM running an emulator. Anyone kn…
... T-states (a T-state is a CPU clock cycle, about 290ns). 224 T-states ... , changing the colour every 224 T-states (or every 64 microseconds) will ...Definitive list of games incompatible with +2A/+3 and of compatible versions (if any)I am trying to compile the definitive list of games which are incompatible with the +2A and the +3 and of their compatible versions, if they are pres…
... measuring where in the frame (t-states) the #FF routine triggers, then ... . This happens at approx ~14500 T-states into a spectrum frame.
T-states, ie if it is entered ... exit at approx 14,500 T-States. It checks for the floating ...Interface 1 - RS232 question.I am thinking about doing some Spectrum stuff based around the RS232 port used on the Interface 1. Has anyone had any joy doing this with an emulator…
... though. It takes approx. 30 t-states to send 1 bit. With ... that's 300 t-states for a byte or 9600 t-states for 32 ... i.e. out of 70k t-states per interrupt. That is approx ... a valid reference. :)
T.Best Z80 Assembler for PC?There's probably already a thread for this so if somebody could please point me at it I'd appreciate it. If there isn't then please respond here wit…
... zmac could help with measuring T-states in contended memory if the ... push af
cost equ t($)-t(start)+$-start[/code]
t(start+3) == t(start) + 13 as "ld a,(n)" takes 13 T-states ... . Arguably t(start+1) should equal t(start) + 4 and t( ...Best Z80 Assembler for PC?There's probably already a thread for this so if somebody could please point me at it I'd appreciate it. If there isn't then please respond here wit…
... /> zmac could help with measuring T-states in contended memory if the ... same number for t(start), t(start+1) and t(start+2) ... t(start+3) == t(start) + 13 as "ld a,(n)" takes 13 T-states ... . Arguably t(start+1) should equal t(start) + 4 and t(start ...Emulator developmentHi, Could anyone explain or direct to a link that explains in not to technical terms how an emulator is developed. It has always blown my mind eve…
... a count of how many T-States that instruction and its values ... . When you've done 69888 T-States (for a 48k Speccy) then ... interrupt, subtract 69888 from your T-State counter, and go back ...New multicolor engine BIFROST*2[img]http://s15.postimg.org/rfue0jb3v/BIFROST2.png[/img] [b]BIFROST*2 ENGINE[/b] is now available! Download it here: https://www.dropbox.com/sh…
... beeper effects in under 10K T's[/quote]
OK ... so, multicolor engines leave 20K T-states free or less (depending on ... many multicolor rows). Spending 10K T-states on beeps is probably too ...Let's copy buffers!Figured I'd do some double buffered graphics, so I can render for several frames before displaying stuff. Yes, I mean on a 48k speccy, so no 128k spe…
... bytes for a few less t-states, is it really worth it ...Let's copy buffers!Figured I'd do some double buffered graphics, so I can render for several frames before displaying stuff. Yes, I mean on a 48k speccy, so no 128k spe…
... really exploiting the full 224 T-states available on a line; certainly ... , where there'd be 20 T-states spare.Manic Miner ported to Atari 800XLYep, they finally ported it :) http://atariage.com/forums/topic/252067-manic-miner-released/
... cartridge to use BASIC) weren't too impressive graphically, from what ... hardware registers, the display isn't memory mapped.
... the fact that there aren't any hardware interrupts to ... its all down to counting t-states.
Which makes ...Manic Miner ported to Atari 800XLYep, they finally ported it :) http://atariage.com/forums/topic/252067-manic-miner-released/
... the fact that there aren't any hardware interrupts to tell ... its all down to counting t-states.[/quote]
Interesting. It ...P.O.W.As far as I know, a port of P.O.W. (Prisoners of War) from NHK, doesn't exist. [img]https://cld.pt/dl/download/61d19b5e-453b-489c-b17b-d3ed6fccd594/…
...
3. In about 69888 T states (frame duration on a 48K ... /> 224 is the number of T states in a single-pixel horizontal ... 20 * 8 * 224 is the T state 'duration' of the active ...P.O.W.As far as I know, a port of P.O.W. (Prisoners of War) from NHK, doesn't exist. [img]https://cld.pt/dl/download/61d19b5e-453b-489c-b17b-d3ed6fccd594/…
... problem is that there isn't enough time in a single ... />
224 is number of T-states in pixel line. What Hikaru ... . Then you have cca 27000 T when writing to screen area ...ZX Dandanator! Mini - Cartridge system for SpectrumsHi All, I'd like to present a little HW I've developed during the last three months. It's aimed at providing a console-like usage experience for a…
... />
CMDLOOP: ; Add extra 110 t-states for ~50us pulse cycle (109 ... all data lines, this doesn't make sense.
I ...Reading sequential key pressesI am thinking about writing a quick game and have an idea that requires me to read alternate key presses. I’m thinking along the lines of Daley Thomp…
... ="joefish;868228"]Another thing - don't wait for a key to ... what I need. I don't think it can be sped ... anyone can shave a few t-states from the key reading / flag ...IXL and IXHI don't know much about undocumented instructions but I get the impression that [b]LD A,IXH[/b] or [b]LD A,IXL[/b] (B, C, D, E also fine, HL not) are…
... HL instruction plus 4 more T-states. That's because they're ... HL instruction plus another 12 T-states. As well as the prefix ...Saving and loading data in assembly.I want to add a save and load feature to an project I'm working on. Since it's not that much data in size I thought I'd use the ROM functions, but ho…
... query the running total using t(address).
Not ... ="http://members.shaw.ca/gp2000/T-states.txt"]table of cycle counts ... />
Unfortunately the assembler doesn't have an output format that ... or something but it isn't exactly clear what's the ...Running out of fingers in AssemblyDear all, Still trying to learn Assembly and have put a few routines together. However, as my routines become a little more involved I find myself…
... storage. Everything you don't currently need in the CPU ... /> Learn how to count T-States and some common optimizations on ... on the Z80, don't use IX and IY ... / instructions take 19 to 23 T-States!
Use HL, BC ... LD A,(HL) is 7 T-States
LD A,(IX+o ...Running out of fingers in AssemblyDear all, Still trying to learn Assembly and have put a few routines together. However, as my routines become a little more involved I find myself…
... class the z80 optimisations and T-state counting as 'intermediate to ... advanced'. Remember, you don't have to learn everything at ... commands
- I didn't count T states or use an interrupt routine ... out that maybe I wouldn't have written such shoddy code ...Running out of fingers in AssemblyDear all, Still trying to learn Assembly and have put a few routines together. However, as my routines become a little more involved I find myself…
... Learn how to count T-States and some common optimizations ... than squeezing a few T-cycles from a poorly ... as said above, don't think of registers as ... intermediate values needed. Don't waste a register pair if ... , storing 5*X isn't necessary: once calculated, you ...Running out of fingers in AssemblyDear all, Still trying to learn Assembly and have put a few routines together. However, as my routines become a little more involved I find myself…
... go. Learn how to count T-States and some common optimizations on ... results than squeezing a few T-cycles from a poorly chosen ...Running out of fingers in AssemblyDear all, Still trying to learn Assembly and have put a few routines together. However, as my routines become a little more involved I find myself…
... loop before you worry about T-States.
And a new assembly ... to run. But it doesn't take very long before a ...Running out of fingers in AssemblyDear all, Still trying to learn Assembly and have put a few routines together. However, as my routines become a little more involved I find myself…
... loop before you worry about T-States.
And a new assembly ... to run. But it doesn't take very long before a ... the "nested loop" solution isn't wasted - nested loops are important ...Mastering flagsI'm little lost when different flags are set/reset after logic operations, and what conditions must be met. For example, [code] ld a, MODE…
... 8 and more T states. Basically everything that isn't RLA/RRA/RLCA ...Optimized (in size) Z80 simulatorI am evaluating Z80 simulators to try to create a tool to analyse z80 programs. I'd like to start with a simple register coverage tool and t-state cy…
... code (or at least show t-states in the editor).
5 ...Must be missing the point - machine code... Hi Folks, Trying my hand at machine code again but falling at the first hurdle. I hand crafted the following to run at address 62000 and the co…
... is 7 t-states
INC L is 4 t-states
... 6144 -5 = 141,307 t-states for the original loop
T-States. That's 26% faster ... Unrolling twice saves 55,296 t-states. That's 39% ... Unrolling again saves 64,512 t-states. That's almost 46% ...Optimized (in size) Z80 simulatorI am evaluating Z80 simulators to try to create a tool to analyse z80 programs. I'd like to start with a simple register coverage tool and t-state cy…
... /> 3) Your two examples don't do the same thing. After ... you know the compiler won't use these kinds of optimization ... ) That should be relatively easy, T-states at least. Proper profiling with ...
