I'LL TAKE THAT!gilesgoat wrote:That's ANOTHER thing ... "an extra" ...Markie wrote:Are we to be mowing lawns sometime soon then?gilesgoat wrote:I fear "someone can't wait to make an annoucement" .. but it's not me .. but I think you'll hear something about it .. soon ..
Oh man, hope it's what I caught a glimpse of last yeargilesgoat wrote: I fear "someone can't wait to make an annoucement" .. but it's not me .. but I think you'll hear something about it .. soon ..
Feel free to expand! :-)Rhythm wrote:Oh man, hope it's what I caught a glimpse of last yeargilesgoat wrote: I fear "someone can't wait to make an annoucement" .. but it's not me .. but I think you'll hear something about it .. soon ..
But classic arcade lawn mowing is pretty exciting isn’t it?Rhythm wrote:Bah, just seen Jeff's latest Tweet and it's probs not what I saw. Dammit
It is, but man do I want the other project to come to fruitionMisfit wrote:But classic arcade lawn mowing is pretty exciting isn’t it?Rhythm wrote:Bah, just seen Jeff's latest Tweet and it's probs not what I saw. Dammit
WHAT THE SMEG IS THIS?
It's a version of Hover Bovver made for Galaxian/Scramble arcade hardware.
WHY'VE YOU MADE THIS YOU DAFT TWONK?
Just for fun. Back in the dawn of time me and the Naughurst Piano Wizard used to go down the Hinds Head in Aldermaston village for a few beers and while there we'd usually play a bit of bar bills and also a few games of whatever was on the cocktail cab in there. It'd usually be some strangeness built on Galaxian/Scramble hardware, I recall playing stuff in there like Checkman, Uniwar S, Scorpion - that kind of thing.
A few years later when we did Hover Bovver I remember thinking it'd've probably gone well on that kind of hardware, I could just imagine playing it on the tabletop cab down the Hinds Head.
Fast forward far too long and I was browsing the web one day and came across the 8bitworkshop.com site where they had an in-browser IDE supporting, amongst other things, Galaxian/Scramble hardware. I had a look and there wasn a little example program that showed how the machine worked.
I pulled that apart to learn for myself, and before I knew it I'd started coding Hover Bovver, in odd spare moments.
IS IT COMPLETE?
In terms of gameplay, pretty much, there are 8 lawns to mow and the traditional Hover Bovver gameplay is there. At the moment there is no audio, in part because when we add audio it'll make the game more machine specific as Galaxian audio is much simpler than Scramble audio.
As it is, the build is near identical for Scramble hardware or Galaxian hardware (with 16k program rom). Eventually we'll do builds for each with sound.
WILL IT WORK ON REAL HARDWARE?
We think it ought! We've actually bought Galaxian and Scramble boards, and we'll be trying it out on those when we can. Galaxian would need modded to run 16k program ROM but that didn't ought to be too hard (Giles says). This ROM runs on the latest MAME, which I would think is a decent indicator that it'll work on real hardware, given that Galaxian/Scramble must be some of the best emulated stuff out there given how old it is and how long it's successfully been emulated.
Enjoy, have fun, let me know if you have any problems with it or find anything in the gameplay egregiously bad, maybe I can fix it.
There's not a huge amount of room to add more, the game is almost full to the 16k brim. I am sure if written in proper assembler it could probably be made to fit in a lot less memory. I have been lazy and just using the C compiler in the 8bitworkshop IDE, which makes for relaxed tinkering but which isn't necessarily optimal.
There are a couple of "hidden bonuses" in the game, "DOGLESS" and "VINDICTIVE". I'll let you find out for yourselves how to get them. Combine them both for maximum bonus points!
And how are you running the game? I'm completely lost lolWhiteball wrote:Come on Giles hurry up with that audio
Must say I like it, but did get cuaght out by the diagonal movement and occasional turn that flung me into the flowers unexpectedly.
Top stuff!
I am GETTING TOTALLY STUPID with the second CPU .. even IF, for our "real HW purpose" I know how I could disable that crap ..Whiteball wrote:Come on Giles hurry up with that audio
Must say I like it, but did get cuaght out by the diagonal movement and occasional turn that flung me into the flowers unexpectedly.
Top stuff!
Code: Select all
void Protection() __naked {
__asm
//
// Invoked from CLEAR_RAM_THEN_JP_0069
//
//
//
push ix
ld ix,#0x421E
ld a,(#0x7000) // kick watchdog
xor a
ld (#0x6801),a // disable interrupts
ld a,#0x9B
ld (#0x8103),a // does nothing
ld a,#0x88
ld (#0x8203),a // does nothing
ld a,#0x08
// ld (#0x4242),a // set IRQTRIGGER_CTRL
ld (#0x8201),a // bit 3 = interrupt trigger on audio CPU
// 007B: 31 00 48 ld sp,$4800
// Protection related code.
// It appears the protection chip needs specific values in a specific sequence to be written to it,
// in order to return a specific value indicating that the protection check succeeded (see $00C0)
//
// I wonder if the protection chip would reset the system if it doesnt get the values written to it in the correct sequence?
// Or would it lock the system completely?
ld a,#0x28
rlca
add a,#0x32
ld h,a
and #0x0F
ld l,a
add a,#0x0D
ld (hl),a // write $0F to protection
ld b,#0x07
ld e,#0x09
_dlp:
ld c,a
ld d,a
djnz _dlp
ld (hl),b // write 0 to protection
// It appears the scramble hardware sets IX to $421E when the system boots up (ie: hits address 0).
ld b,#0x03
_rdlp: ld c,3(ix) // read from $4221
djnz _rdlp
ld (hl),a // write $0F to protection
ld e,c
ld (hl),b // write 0 to protection
ld b,#0xFA
add a,b
ld (hl),a // write $09 to protection
ld c,#0x10
ld b,#0x20
add a,c
add a,b
ld e,(hl) // reads $F9 from protection...
ld a,#0xF0
and e // produces $F0..
cpl // produces $0F..
and #0xF0 // produces 0. Or should do - if it doesn't, protection kicks in.
// 00AE: C0 ret nz ; return if protection is triggered. Someone's hacking.
ld h,#0x82
ld a,h
and #0x3F
ld l,a // set HL to $8202 (protection)
ld (hl),#0x0A // write 10 to protection
add a,#0x02
ld (hl),a // write 4 to protection
add a,#0x05
ld (hl),a // write 9 to protection
ld a,(hl) // reads $B9 from protection check
and #0xF0 // produces $B0
cp #0xB0 // compare to $B0, which is value if protection check succeeds
// 00C2: C2 DC 05 jp nz,$05DC ; if protection check does not succeed, corrupt memory state by jumping to text strings, not code..
// When we get here, the preliminary protection checks have passed.
ld a,(#0x7000) // kick watchdog
xor a
inc a
ld (#0x6801),a // enable interrupts
pop ix
ret
__endasm;
}
I tossed the zip file into the ROMs directory of MAME. Seeing as it was named Scramble I chose Scramble from the MameUI games list and ran that. It grumbled a bit about the ROM being wrong but then ran it with no complaints.Markie wrote:And how are you running the game? I'm completely lost lolWhiteball wrote:Come on Giles hurry up with that audio
Must say I like it, but did get cuaght out by the diagonal movement and occasional turn that flung me into the flowers unexpectedly.
Top stuff!
You get the ROMs file ( or you zip ALL the individual rom files ) into "scramble.zip" then you put into the "roms" directory of MAME ( of course you'll need to re-name the original scramble.zip ROM into something like "scramble-orig.zip" if you don't want to loose it.Markie wrote:And how are you running the game? I'm completely lost lolWhiteball wrote:Come on Giles hurry up with that audio
Must say I like it, but did get cuaght out by the diagonal movement and occasional turn that flung me into the flowers unexpectedly.
Top stuff!
