Spectrum Computing

Well, either way, here it is, just give it the RCS encoded screen address in HL ld bc,4000h ;screen address lp1: ld a,b cp 5bh ret z cp 58h jr nc,skip xor c and 0f8h xor c ld d,a xor b xor c rlca rlca ld e,a skip: ldi inc bc inc bc jr lp1 27 bytes or 96 when used along with deZX0

Einar, having just browsed your GitHub stuff in greater detail, it seems you’re missing the smaller RCS decoder that I put on WOS some years ago, weighing in at 27 bytes. If you don’t have it, I’ll give you the code if you like?

Having read the stuff on GitHub, am I correct that zx0 has the ability to utilise a ‘dictionary’ at a different location to where the code decompresses?

This really is wonderful. Any chance of an overview of the compression methods?

Yes, it suddenly occurred to me that it was so much smaller to code, and there is only 8 bytes of date, two of which are an 06, 04 (ld b,04) at the start of a routine, so technically 6 bytes only.

This is the new routine to set the board; init_board: ld de,data20 ld hl,0ffc0h ib1: ld bc,0602h ld a,(de) ld (hl),a inc e ib2: inc l ld (hl),c ld c,00h djnz ib2 ib3: ld (hl),03h inc l inc a ld (hl),a inc l jr nz,ib1

Yes! Development has definitely slowed, but it has continued.

The board initialise routine is now 26 bytes with 6 bytes of data

Oh dear!! I always seem to have a habit of premature posting when I think I’ve done something good!

Well, actually I’ve saved more than I thought!

Now

497 bytes!

Now I really didn’t expect to save a whopping 6 bytes!!

Can’t wait to try this! I need to dust off the old toastrack and fire her up!! Looks incredible.

Christmas cheer to all! After almost an entire year of faffing around trying desperately to save an odd byte here and there and failing, I woke up yesterday morning and came up with a Solution to save 4 bytes!! ..so now my little chess thing has now broken the 500 byte milestone. 499 bytes! I’ll pos...

No problem Peter, time flies and all that!!

I think they can be applied to all the 8 bit registers.

Not sure if any of these might help. Found these in my archives. Next Line down WRT HL --------------------- 24 inc h 7C ld a,h E607 and $07 200A jr nz,end 7D ld a,l C620 add a,$20 6F ld l,a 3805 jr c,end 7C ld a,h D608 sub $08 67 ld h,a 16 bytes Next Line Down Circa 1998 Spencer Winset ------------...

Oh how I used to love those microfairs!! At the horticultural halls in Westminster if I recall correctly?! Great places to meet the programmers and surprise that my dad knew more than one of them!!!!

Generally the blocks are printed from the furthest away first, then the ones in front overwrite what lies behind them. In some cases there are checks to negate printing stuff that will eventually not be seen, but in the interests of speed, that’s often overlooked.if you look at one of the animated g...

No need to worry about iy. But being able to use one of the alternative register pairs for addressing instead of Ix may give the possibility of saving a few bytes.

Just HL’ ?

Quick question that someone might be able to answer for me, as I’m not in the vicinity of a speccy or emulator to test. When calling a routine from basic (rand usr etc) does using the alternative registers set (exx) cause issues upon the RET? Would the always need to be pushed prior to messing with ...

2100 is pushing it a bit. Chess has taken since about 1993 to get to where it currently is :D I did adapt the routines that draw the chess board (well, the addressing part anyway) to be used as an isometric room builder, with a compressed block printing routine. That would allow for an isometric gam...

Very kind of you to say so :) I’ve been in awe of Alex’s ChessKelet development for a while now. In fact, what he’s achieved way outshines my efforts, but remains a massive inspiration and guiding light for my future developments. The reason I keep on with the squashing of C2k18 is that as I find wa...

A coming together and shifting about of two other key routines (might) give the possibility of saving one or perhaps two more bytes too. More time tomorrow, so I’ll get my abstract thinking cap on. Sometimes it’s a case of looking at how things work from a different point of view, so as to figure ou...

Afternoon all!

Been a while, but whilst I’ve a few days off I thought I’d try out a couple of ideas. However, as I was refreshing everything in my brain, I managed to save another byte on the display engine. Bit boring maybe, but it is now 503 bytes.

Ello?!

Sorry, seems I’ve been very uncommunicative of late. Been busy with new job and don’t get time to do what I love with speccy things any more. I’m at your service Sir!

Possibly a feature that could be optional. That’s actually not very difficult to implement, but could be a long process when a lot of moves are possible. Move generation is completely separate to the display and piece building part.

Mmmmmmmm maybe, and a click might enhance things.