peteym5 Posted November 18, 2015 Share Posted November 18, 2015 (edited) I am attempting to set up this game to assemble both the 8-bit machines and the Atari 5200. The Game will have elements from Asteroids. Current working title is Megaoids because part of the game is that you have to destroy bases in asteroids fields, or blow up the asteroids itself. Take multiple shots to blow up a mega size asteroid with a base. I am still working out the details. The 8-bit version will be geared to run on computer with 16K present (600XL, or 400 with 16K) to a 130XE. The 5200 will need to run from a 16K cartridge. Both are being set up to only use the first 16K of RAM that is common on all machines. Of course I cannot publicly display the full source code at this time. Will need to do that through private messenger and email, along with the persons word that they will not share code. It is still less than half done. LDX SHIPDIR LDA TABSIN,X AND #127 ASL @ STA M0 LDA TABCOS,X AND #127 ASL @ STA M1 IFT CartridgeType = CartridgeStandard16K LDA PORTA AND #$0F ELI CartridgeType = CartType520016K||CartridgeType = CartType520016K2 ;Need Code for 5200 Here EIF LSR @ TAY BCC THRUST_SHIP_HOZ JMP NOT_JOYSTICKUP THRUST_SHIP_HOZ LDX SHIPDIR LDA TABSIN,X BMI SHIP_HOZ_LEFT BIT SHIPDELTADR BVS SUB_SHIP_HOZ CLC ADC SHIPDELTAXL STA SHIPDELTAXL BPL NO_RITE_DELTA_INC AND #127 STA SHIPDELTAXL LDA SHIPDELTAXH CLC ADC #4 CMP M0 BCC NO_RITE_MAX LDA M0 NO_RITE_MAX STA SHIPDELTAXH NO_RITE_DELTA_INC LDA SHIPDELTADR AND #191 ORA #1 STA SHIPDELTADR JMP THRUST_SHIP_VERT SUB_SHIP_HOZ AND #127 STA M2 LDA SHIPDELTAXL SEC SBC M2 STA SHIPDELTAXL BPL NO_SHIP_RITE_REV_DEC AND #127 STA SHIPDELTAXL LDA SHIPDELTAXH SEC SBC #4 BCS NO_SHIP_RITE_REV_DEC LDA SHIPDELTADR AND #191 ORA #1 STA SHIPDELTADR LDA #0 NO_SHIP_RITE_REV_DEC STA SHIPDELTAXH NO_SHIP_RITE_REV JMP THRUST_SHIP_VERT SHIP_HOZ_LEFT AND #127 STA M2 BIT SHIPDELTADR BVC ADD_SHIP_HOZ CLC ADC SHIPDELTAXL STA SHIPDELTAXL BPL NO_LEFT_DELTA_INC AND #127 STA SHIPDELTAXL LDA SHIPDELTAXH CLC ADC #4 CMP M0 BCC NO_LEFT_MAX LDA M0 NO_LEFT_MAX STA SHIPDELTAXH NO_LEFT_DELTA_INC LDA SHIPDELTADR ORA #65 STA SHIPDELTADR JMP THRUST_SHIP_VERT ADD_SHIP_HOZ LDA SHIPDELTAXL SEC SBC M2 STA SHIPDELTAXL BPL NO_SHIP_LEFT_REV_DEC AND #127 STA SHIPDELTAXL LDA SHIPDELTAXH SEC SBC #4 BCS NO_SHIP_LEFT_REV_DEC LDA SHIPDELTADR ORA #65 STA SHIPDELTADR LDA #0 NO_SHIP_LEFT_REV_DEC STA SHIPDELTAXH THRUST_SHIP_VERT LDA TABCOS,X BPL SHIP_HOZ_UP BIT SHIPDELTADR BMI SUB_SHIP_VRT AND #127 CLC ADC SHIPDELTAYL STA SHIPDELTAYL BPL NO_DOWN_DELTA_INC AND #127 STA SHIPDELTAYL LDA SHIPDELTAYH CLC ADC #4 CMP M1 BCC NO_DOWN_MAX LDA M1 NO_DOWN_MAX STA SHIPDELTAYH NO_DOWN_DELTA_INC LDA SHIPDELTADR AND #127 ORA #1 STA SHIPDELTADR JMP THRUST_SHIP_DONE SUB_SHIP_VRT AND #127 STA M2 LDA SHIPDELTAYL SEC SBC M2 STA SHIPDELTAYL BPL NO_SHIP_DOWN_REV AND #127 STA SHIPDELTAYL LDA SHIPDELTAYH SEC SBC #4 STA SHIPDELTAYH BCS NO_SHIP_DOWN_REV LDA SHIPDELTADR AND #127 ORA #1 STA SHIPDELTADR LDA #0 NO_SHIP_DOWN_REV STA SHIPDELTAYH JMP THRUST_SHIP_DONE SHIP_HOZ_UP AND #127 STA M2 BIT SHIPDELTADR BPL ADD_SHIP_VRT CLC ADC SHIPDELTAYL STA SHIPDELTAYL BPL NO_UP_DELTA_INC AND #127 STA SHIPDELTAYL LDA SHIPDELTAYH CLC ADC #4 CMP M1 BCC NO_UP_MAX LDA M1 NO_UP_MAX STA SHIPDELTAYH NO_UP_DELTA_INC LDA SHIPDELTADR ORA #129 STA SHIPDELTADR JMP THRUST_SHIP_DONE ADD_SHIP_VRT LDA SHIPDELTAYL SEC SBC M2 STA SHIPDELTAYL BPL NO_SHIP_UP_REV AND #127 STA SHIPDELTAYL LDA SHIPDELTAYH SEC SBC #4 BCS NO_SHIP_UP_REV LDA SHIPDELTADR ORA #129 STA SHIPDELTADR LDA #0 NO_SHIP_UP_REV STA SHIPDELTAYH THRUST_SHIP_DONE NOT_JOYSTICKUP TYA LSR @ TAY BCS NOT_JOYSTICKDOWN NOT_JOYSTICKDOWN LDA PORTA AND #$0C LSR @ LSR @ TAX LDA SHIPDIR CLC ADC MINUS_PLUS_STICK,X CMP #240 BCC NO_SHIPDIR71 LDA #71 NO_SHIPDIR71 CMP #72 BCC NO_SHIPDIR0 LDA #0 NO_SHIPDIR0 STA SHIPDIR LDA SHIPDELTADR BEQ SHIP_NO_MOVE LDA SHIPYLO BIT SHIPDELTADR BPL SHIP_MOVE_DOWN SHIP_MOVE_UP SEC SBC SHIPDELTAYH STA SHIPYLO BCS NO_SUB_YH DEC SHIPYHI NO_SUB_YH JMP CHECK_SHIP_HOZ SHIP_MOVE_DOWN CLC ADC SHIPDELTAYH STA SHIPYLO BCC NO_ADD_YH INC SHIPYHI NO_ADD_YH CHECK_SHIP_HOZ LDA SHIPXLO BIT SHIPDELTADR BVC SHIP_MOVE_LEFT SHIP_MOVE_RIGHT SEC SBC SHIPDELTAXH STA SHIPXLO BCS NO_SUB_XH DEC SHIPXHI NO_SUB_XH JMP SHIP_NO_MOVE SHIP_MOVE_LEFT CLC ADC SHIPDELTAXH STA SHIPXLO BCC NO_ADD_XH INC SHIPXHI NO_ADD_XH SHIP_NO_MOVE LDA FIREAGAIN BEQ NO_FIREAGAIN_DEC DEC FIREAGAIN NO_FIREAGAIN_DEC IFT CartridgeType = CartridgeStandard16K LDA TRIG0 BEQ PRESSING_FIRE ELI CartridgeType = CartType520016K||CartridgeType = CartType520016K2 ;Need Code for 5200 Here EIF JMP DO_FIRE_RESET PRESSING_FIRE LDA FIREAGAIN BEQ ALLOW_BOLT_FIRE JMP NO_FIRE_RESET ALLOW_BOLT_FIRE LDA #2 STA M0 BOLT_AGAIN_LOOP LDY FIREBOLTNUM INY CPY #3 BCC NOFIREBOLT0 LDY #0 NOFIREBOLT0 STY FIREBOLTNUM LDA BOLTSTATUS,Y BEQ FIRE_THIS_BOLT DEC M0 BNE BOLT_AGAIN_LOOP JMP NO_FIRE_RESET FIRE_THIS_BOLT LDA #32 STA BOLTSTATUS,Y LDA SHIPDIR TAX CMP #36 BCC NOBOLTHLF SBC #36 NOBOLTHLF CLC ADC #74 STA BOLTIM,Y STA BOLTDIR LDA SHIPXHI STA BOLTSX,Y LDA SHIPYHI STA BOLTSY,Y LDA TABSIN,X AND #127 STA BOLTDXL,Y ;STA M0 LDA BLTSIN,X STA BOLTDXH,Y Edited November 18, 2015 by peteym5 Quote Link to comment Share on other sites More sharing options...
Bryan Posted November 18, 2015 Share Posted November 18, 2015 Thinking back, the main things I needed to do were: 1. Define an assembler flag to pick which system you're building for. 2. Include one of 2 files to define the register name/locations 3. Ditto for vectors and any other RAM functions the systems have in common 4. If you need any OS function not provided in the 5200, you need to have an equivalent routine to assemble into the 5200 build (MULE used floating point, so my 5200 build included support for it) 5. Write 2 routines to handle sticks and other inputs and include the one you need. Umm.. that's about it except for small data sections to make the cartridge init stuff work. 1 Quote Link to comment Share on other sites More sharing options...
phaeron Posted November 18, 2015 Share Posted November 18, 2015 Never actually had a chance to code on the real hardware, but I've seen more than enough in emulation already: The 5200 OS does not clear RAM. Make sure you do so explicitly. Be careful with DLI timing. The 5200 OS has an extra STA NMIRES prior to calling through (VDSLST), which has been problematic on ports of 8-bit games with DLI handlers that have tight stage 1 timing. Decimal mode is not cleared before invoking the VBI handler. Only CRITIC is checked by VBI, not the I flag. If you have code bracketed with SEI/CLI to guard changes to shadow variables or to temporarily shield changes from the deferred VBI, you'll need to modify it to use INC CRITIC/DEC CRITIC. The 5200 joysticks require keyboard debounce to be off to read the keypads. If you write SKCTL=$03 instead of $02, the keypads will not work. Similarly, SKSTAT bit 2 also acts differently and will pulse about 7 times a frame for a held button. Not all emulators emulate this. 2 Quote Link to comment Share on other sites More sharing options...
Rybags Posted November 18, 2015 Share Posted November 18, 2015 Some aspects of processing like VBlank and controller input handling are so different that IMO it'd be better to just have entirely seperate conditional assembly of such routines. Also, that printer effect listing is impossible to read with the "deflection" theme (dk grey) that I'm using. 1 Quote Link to comment Share on other sites More sharing options...
Bryan Posted November 18, 2015 Share Posted November 18, 2015 Also, that printer effect listing is impossible to read with the "deflection" theme (dk grey) that I'm using. Ah, now we know how to hide things from you! Quote Link to comment Share on other sites More sharing options...
peteym5 Posted November 18, 2015 Author Share Posted November 18, 2015 If someone wants to help me with this, send me a private message and I can put the source into a zip and you can see what is going on so far. Quote Link to comment Share on other sites More sharing options...
peteym5 Posted June 8, 2017 Author Share Posted June 8, 2017 I have figured out some memory layout for the cartridges and what RAM locations used by the 5200 in Page 0 and Page 2. I can actually discard my own custom Real Time Clock code because many of my ML games bypass the 8-bit OS VBIs, NMI, and DLI routines. I discovered there are 2 16K cartridge memory layouts for the 5200. The One 16K chip version is mapped from $8000 to $BFFF just as the 8-bit counter part. The two chip one is a little trickier to program. Has 1st chip $4000 to $5FFF then repeated $6000 to $7FFF, then 2nd chip mapped from $8000 to $9FFF and repeated $A000 to $BFFF. What I had to do is insert extra "ORG" directive after the last RTS right before $A000 to make sure a routine does not cross a boundary. A few things had to be re-sorted. We are working on figuring out reading the 5200 controllers. I know there was a few after market joystick made by 3rd parties. Was the self-centering issue ever solved? Quote Link to comment Share on other sites More sharing options...
peteym5 Posted June 9, 2017 Author Share Posted June 9, 2017 (edited) Well I managed to get the title screen up for Delta Space Arena on the Atari 5200 in the emulator. None of the console buttons are working yet. The 5200 immediate ROM VBI is much shorter than the 8-bit version and uses 0 page locations for shadows, so I don't have to bypass it and duplicate the function of the real-time clock. I use many DLIs so shadow color registers are not used much. I have someone helping me with reading the controller and having it control things in the game. Edited June 9, 2017 by peteym5 1 Quote Link to comment Share on other sites More sharing options...
peteym5 Posted June 14, 2017 Author Share Posted June 14, 2017 I am in the process of porting the 8 planned 16K games that I made for the Atari 8-bit computer. Amok Bots, Delta Space Arena, Laser Blast, Megaoids had already been released for the 8-bit. 4 more games will be released within a year. All these were geared toward being played on a 16K computer, although 99% of owners have 64K machines. That was to make sure the games could one day be ported to the 5200. I am also doing my own port of the 5200 Venture. I was disturbed that a hacker took our names were taken off the credits. Secretum Labyrinth Kings Gold is also being considered. Quote Link to comment Share on other sites More sharing options...
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