Loxley

[worldxxisoft]

how was this sound done in basic!!??

Early versions of the game featured square wave sounds by poking the channels, like:
POKE 23739,1: POKE 23740,6: PRINT "0 0 00 00 000 000"; so the PRINT output goes to the BEEPER (port 254) instead of screen.

You can find info about its development in: (Spanish spoken, English text)
https://www.youtube.com/watch?v=FyVZ59XIWwI
(Around 14:00 you can see a square wave sound test program)

The final version features AY sounds (with registers), square wave sounds (beeper) and sine wave sounds (AY), with RLE compression achieved by poking the stack to call ROM routines in sequence. You can find additional info in https://bytemaniacos.com/ficheros/concu ... ey_doc.txt

[pavero]

How to solve this puzzle?



https://maps.speccy.cz/temp/loxley.z80

[Andre Leao]

You can jump to the right. Pixel perfect

[presh]

Gave this a proper go yesterday... brilliant!

Managed to finish the game on easy, but haven't managed to figure out some of the puzzles...

One has 3 "bullseye" targets and a snake on the floor. I can hit all the targets, but the ladder doesn't drop. I've tried shooting them in different orders. There are some shields on the wall, not sure if this a clue or if they're just decorative.

The other puzzle room has a rat (?) which you can move by shooting near it, and some yellow blocks which disappear when shot. (I managed the other room with the rat, but can't figure this one out!!)

...help?

[pavero]

I solved all puzzles in my RZX.

https://spectrumcomputing.co.uk/zxdb/ad ... ry_rzx.php

[presh]

I solved all puzzles in my RZX.

https://spectrumcomputing.co.uk/zxdb/ad ... ry_rzx.php

Cheers, though I'd rather take a few tips/pointers and try to figure them out myself... e.g. "the order of hitting the targets is/isn't important" "the shields do/don't mean anything" "you need to shoot some of the yellow blocks but not others", that kinda thing, if anyone would be so kind!

I feel like I'm mostly there, but possibly overthinking or just being dumb

[pavero]

One has 3 "bullseye" targets and a snake on the floor. I can hit all the targets, but the ladder doesn't drop. I've tried shooting them in different orders. There are some shields on the wall, not sure if this a clue or if they're just decorative.

The correct order is the key. There are 3! (factorial) of combinations.

The other puzzle room has a rat (?) which you can move by shooting near it, and some yellow blocks which disappear when shot. (I managed the other room with the rat, but can't figure this one out!!)

You must get the rat to the "bullseye" target.

[worldxxisoft]

Thanks presh and pavero for the questions and answers, when I released the v1.0 there were 4 targets and I thought the combinations where 2 ^ 4 = 16, but then I realised the combinations were 4! = 1 * 2 * 3 * 4 = 24 combinations, more difficult than I intended, so in v1.1 I left just 3 targets, 3! = 1 * 2 * 3 = 6 combinations, much easier...

Spoilers ahead... regarding the other questions...

Spoiler

- Regarding rats and blocks, if you don't want to see walkthroughs, it's just a matter of clearing path by shooting blocks and leave those blocks needed to stop the movement of the rat and guide it to the bullseye.
- Regarding shields (those colourful emblems in front of buildings), they are just decorative.
- Although it hasn't been asked, just remind the game has some RPG flavors, meaning it's important to improve Robin' sword and bow skills as much as possible before going to Nottingham, as there are strong enemies there. Also, it's a lot easier to kill regular enemies when skills are high or maxed out.

[patters]

I have finally given this a try and it's absolutely astounding. I can't believe the lack of comments on the itch.io page. I struggle to see how anyone will ever top this technical achievement for the Spectrum.

Regarding the discussed use of LDIR RET from the ROM, how are the CPU register values for the LDIR operation populated from BASIC?

[worldxxisoft]

Hi Patters, thanks for the question and support.
You can populate CPU registers by sequentially calling ROM routines containing POP instructions which read the parameters from a crafted stack.

I prepared an example which transfers an SCREEN$ located in 42240 to 16384, using only ROM calls without any machine code execution in RAM, I hope you find it useful to understand the concept, let me know if you have any questions:

Code: Select all

  1 REM   EXECUTE IN 48K MODE
 10 CLEAR 39999
 15 REM   POKE STACK
 20 FOR   F=40000 TO 40017: READ A: POKE F,A: NEXT F
 30 DATA  069,026: REM #1A45 POP HL,DE
 40 DATA  000,165: REM #A500 42240
 50 DATA  000,064: REM #4000 16384
 60 DATA  246,012: REM #0CF6 POP BC
 70 DATA  000,027: REM #1B00 6912
 80 DATA  195,051: REM #33C3 LDIR
 90 DATA  166,016: REM #10A6 POP HL
100 DATA  058,156: REM #9C3A 40000-6 
110 DATA  047,016: REM #102F LD SP,HL
190 REM   POINT LSTSP TO 40000
200 POKE  23615,64: POKE 23616,156
210 RANDOMIZE USR 9499:: REM DI
220 RANDOMIZE USR 3197 : REM LD SP,(LSTSP)
230 RANDOMIZE USR   81 : REM EI

In z80 format:
https://drive.google.com/file/d/1tRNvRh ... sp=sharing