Search found 308 matches

by RMartins
Thu May 24, 2018 5:41 pm
Forum: Programming
Topic: Beginner's ASM Tutorial: Multiplatform Z80 ASM development videos... with vampires!
Replies: 45
Views: 2073

Re: Beginner's ASM Tutorial: Multiplatform Z80 ASM development videos... with vampires!

Just a correction, for the Swap instructions, we need 4 instructions, not 2:

Code: Select all

EX AF, AF'
EXX

... do the interrupt magic here

EX AF, AF'
EXX
Which is ( 4 + 4 ) + ( 4 + 4 ) = 16T
Still a long way from the 88T for the PUSH/POP solution.
by RMartins
Thu May 24, 2018 1:01 pm
Forum: Programming
Topic: Beginner's ASM Tutorial: Multiplatform Z80 ASM development videos... with vampires!
Replies: 45
Views: 2073

Re: Beginner's ASM Tutorial: Multiplatform Z80 ASM development videos... with vampires!

It's quite curious how the different systems use the shadow registers in my game, I use DI/EI when I use the shadow registers in a normal loop, but two EXX 'es and DI/EI are pretty much the same speed as a PUSH/POP, so there's rarely any cases it's worthwhile. it seems interrupt handlers on most do...
by RMartins
Thu May 24, 2018 10:10 am
Forum: Brand new software!
Topic: Work in progress - Power Blade - The next Sanchez blockbuster?!
Replies: 13
Views: 363

Re: Work in progress - Power Blade - The next Sanchez blockbuster?!

Looks really interesting, with nice graphics.

The movement, of the character is well hidden, within the char limit for color clash.
by RMartins
Thu May 24, 2018 10:07 am
Forum: Programming
Topic: Basic VAL function
Replies: 15
Views: 172

Re: Basic VAL function

It's to save memory, since in BASIC representation, VAL "256", takes less bytes to represent the number 256 directly. This saves memory, if you are really tight on it, but it's slower. So it's a compromise, that can be used on code that does not run often, or is just part of the loader for example. ...
by RMartins
Tue May 22, 2018 5:05 pm
Forum: Emulators
Topic: Testing emulators using z80test-1.0. Quck results
Replies: 22
Views: 268

Re: Testing emulators using z80test-1.0. Quck results

OK, then a great test to do, is save the app into a snapshot after break, and then run it on a real Spectrum, using DIVIde, DivMMC or similar.

I'm curious to run this on the ZX Next too :)
by RMartins
Tue May 22, 2018 4:32 pm
Forum: Emulators
Topic: Testing emulators using z80test-1.0. Quck results
Replies: 22
Views: 268

Re: Testing emulators using z80test-1.0. Quck results

Independently of the quality of the test tool, it might have some specific dependency on a specific instruction, that if it fails, it might trigger a lot of other fails. What I mean, is a simple fail, might trigger a lot more fails, because the test tool relies on that specific bad instruction, to m...
by RMartins
Tue May 22, 2018 2:43 pm
Forum: Emulators
Topic: Testing emulators using z80test-1.0. Quck results
Replies: 22
Views: 268

Re: Testing emulators using z80test-1.0. Quck results

There are some inconsistent results too Running `Z80Full.tap` Gives 002 errors, for example. and I see that instruction INC RR an INC XY (apparently they are different things (could it be second is for iX and iY ?) are returned as OK. But these return as errors, when running `Z80ccf.tap` It's not ru...
by RMartins
Tue May 22, 2018 2:34 pm
Forum: Emulators
Topic: Testing emulators using z80test-1.0. Quck results
Replies: 22
Views: 268

Re: Testing emulators using z80test-1.0. Quck results

Which instruction are these ?

ALO A, A
ALO something

SLIA A

SRO (xy)
by RMartins
Tue May 22, 2018 2:07 pm
Forum: Emulators
Topic: Testing emulators using z80test-1.0. Quck results
Replies: 22
Views: 268

Re: Testing emulators using z80test-1.0. Quck results

The description of Zero 0.7.1 says 005 but the image states only 3 errors.
by RMartins
Fri May 18, 2018 3:02 pm
Forum: Preservation
Topic: Reverse engineering "Stack Light Rifle"
Replies: 14
Views: 340

Re: Reverse engineering "Stack Light Rifle"

I'm convinced the circuit will be very similar to the one on the Magnum Light Phaser. They are. The interior of the gun is well documented. I just need the interior/pinout of the connector. Yes, I am aware they just work with CRTs. You guys would be surprised to know how many of us still have one o...