Search found 27 matches

by utz
Sat Nov 11, 2017 5:45 pm
Forum: Showcase
Topic: WOOT! XMas Tape Magazine
Replies: 5
Views: 2300

Re: WOOT! XMas Tape Magazine

Hi R-Tape, Only saw this post now. I hope I can find some free time to whip up a little beeper tune. Also, just checked out Issue 0, and I think I can answer the question in the letter from "A Beepola User, Lancaster": To control the note length in Beepola, you can use key A, which inserts a "note-o...
by utz
Fri Oct 06, 2017 11:05 pm
Forum: Showcase
Topic: bintracker - new ZX beeper music editor
Replies: 5
Views: 1630

Re: bintracker - new ZX beeper music editor

Not mine, Shiru's Tritone ;) The faster speed would indeed help to reduce noise (or make it less annoying, at least), though anything up to 224 cycles should be ok. For further noise reduction, the distance between all port writes should be a multiple of 8 cycles.
by utz
Wed Sep 27, 2017 7:48 pm
Forum: Showcase
Topic: bintracker - new ZX beeper music editor
Replies: 5
Views: 1630

Re: bintracker - new ZX beeper music editor

AA: Thanks, your star makes the repo shine ;) Btw 'm thinking to add the z88dk version of Tritone, though generally I don't plan on adding engines that are already available in 1tracker and/or Beepola. First I need to rewrite libmdal (which does the user input to asm data translation) though, as it'...
by utz
Thu Sep 21, 2017 3:28 pm
Forum: Showcase
Topic: bintracker - new ZX beeper music editor
Replies: 5
Views: 1630

bintracker - new ZX beeper music editor

Not exactly Next related, but it might be useful for Next users all the same! Bintracker is a new PC-based music editor, targetting the Spectrum (and beyond in the future). For now it supports a handful of my latest beeper music engines. It's open source, and runs on Windows and *nix. The latest rel...
by utz
Wed Sep 13, 2017 8:59 am
Forum: Showcase
Topic: The Spectrum Next Digital Audio Workstation
Replies: 5
Views: 4035

Re: The Spectrum Next Digital Audio Workstation

Wow, that looks great indeed. In fact, it looks like this might become my favourite toy on the Next.
by utz
Sun Aug 06, 2017 4:58 pm
Forum: Z80 Assembly
Topic: Adding an 8-bit signed number to a 16-bit number
Replies: 10
Views: 2840

Re: Adding an 8-bit signed number to a 16-bit number

Har har har, that's gotta be the most evil z80 trick I've seen in a while! Brilliant, thanks a ton!
by utz
Sun Aug 06, 2017 2:35 pm
Forum: Z80 Assembly
Topic: Adding an 8-bit signed number to a 16-bit number
Replies: 10
Views: 2840

Re: Adding an 8-bit signed number to a 16-bit number

Neat, that's actually 1t or so faster than the version I have (using jp) ;) SMC would be acceptable, relocatability is not needed. Actually I realize now that I asked the wrong question. I don't need HL+-E, I need HL +- [a value from memory]. Hence the need for jump-less, since I'd want to squeeze i...
by utz
Sun Aug 06, 2017 12:56 pm
Forum: Z80 Assembly
Topic: Adding an 8-bit signed number to a 16-bit number
Replies: 10
Views: 2840

Re: Adding an 8-bit signed number to a 16-bit number

Ah, right, it should be jr nc. While we are on the topic of math routines, I need one, too (hope you don't mind me hijacking your thread, hyphz). What I need is a routine that will do either HL+E or HL-E depending on the state of the carry flag. The routine should be jump-less, have a fixed cycle co...
by utz
Sat Aug 05, 2017 9:11 pm
Forum: Z80 Assembly
Topic: Adding an 8-bit signed number to a 16-bit number
Replies: 10
Views: 2840

Re: Adding an 8-bit signed number to a 16-bit number

Not pretty, but also needs no extra registers:

Code: Select all

   rlca
   jr nc,skip
   dec h
skip
   rrca
   add a,l
   ld l,a
   adc a,h
   sub l
   ld h,a
by utz
Sat Aug 05, 2017 12:48 pm
Forum: ZX Spectrum Next
Topic: Normalising interrupts, math coprocessor?
Replies: 13
Views: 1519

Re: Normalising interrupts, math coprocessor?

Ha, thanks for all the credit, guys :D However, I have to admit that I can't be of much help with this. For one, I'm notoriously bad with maths. Also, in the world of beeper, we don't worry too much about this, as it's already difficult enough to do even a linear slide given the timing constraints. ...