Just Jeff Posted December 20, 2018 Author Share Posted December 20, 2018 Done! Thanks Thomas. I followed the link, but understood almost none of it even with the DASM manual by my side. I'm sure it would have to be heavily commented for me to follow it better. Quote Link to comment Share on other sites More sharing options...
Just Jeff Posted December 20, 2018 Author Share Posted December 20, 2018 So of those EF could be made to work with my example. As Thomas mentions, if you do it this way the overhead increases (as more of each 4K bank is dedicated to bank switching code) so finding a better way to do it would be in your best interesting. One side affect of my switching to ARM support for my games is they only use 1 bank of 6507 code, and the ARM sees everything without needing to bankswitch, so I've not looked into better ways to do it. Thinking about this some more, I thought of a way to greatly reduce the overhead. I'm curious to know if this will work. If I were to expand to 16 banks of 4K, 12 of these banks would be kernels and therefore, would always return to "Overscan" in the jump table. Couldn't I move "Overscan to the top of JUMP_TABLE, then delete the remainder the jump table that follows "Overscan" in those 12 banks? Further, couldn't I get rid of all but the last SelectBank in BANKS_AND_VECTORS in those 12 banks, always jumping to the last bank? (Which doesn't get me to "Overscan" right now but I suppose I could move Overscan to the last bank.) These changes would probably also apply to the voice banks as well, leaving only one bank requiring the full JUMP_TABLE and BANKS_AND_VECTORS macros. Does that work? MAC JUMP_TABLE ; start of every bank RORG $F000 SystemStart ; inititialize system nop SelectBank1 jmp SystemStartCode MCP ; game logic nop SelectBank1 jmp MCPCode Overscan nop SelectBank1 jmp OverscanCode IntroKernels ; kernels nop SelectBank2 jmp IntroKernelsCode Kernels3 ; kernels nop SelectBank3 jmp Kernels3Code Kernels4 ; kernels nop SelectBank4 jmp Kernels4Code Voice1 ; voice bank 1 nop SelectBank5 jmp Voice1Code Voice2 ; voice bank 2 nop SelectBank6 jmp Voice2Code Voice3 ; voice bank 3 nop SelectBank7 jmp Voice3Code Voice4 ; voice bank 4 nop SelectBank8 jmp Voice4Code ENDM MAC BANKS_AND_VECTORS ; end of every bank RORG $FFF4 SelectBank1 .byte $00 SelectBank2 .byte $00 SelectBank3 .byte $00 SelectBank4 .byte $00 SelectBank5 .byte $00 SelectBank6 .byte $00 SelectBank7 .byte $00 SelectBank8 .byte $00 Quote Link to comment Share on other sites More sharing options...
Just Jeff Posted December 20, 2018 Author Share Posted December 20, 2018 Wait.. That doesn't work does it. The program counter will be in the wrong place. 1 Quote Link to comment Share on other sites More sharing options...
+SpiceWare Posted December 21, 2018 Share Posted December 21, 2018 BANKS_AND_VECTORS would need to be in every bank, so that wouldn't change. An easy way to split the jump table would be to have Overscan and Vertical Blank in different banks. Vertical Blank needs to call the kernels, so have Overscan handle the voice routines. MAC JUMP_TABLE_OS_V ; start of Overscan and Voice banks RORG $F000 SystemStart ; inititialize system nop SelectBank1 jmp SystemStartCode VerticalBlank ; game logic (Vertical Blank) nop SelectBank5 jmp VBCode Overscan nop SelectBank1 jmp OverscanCode Voice1 ; voice bank 1 nop SelectBank2 jmp Voice1Code Voice2 ; voice bank 2 nop SelectBank3 jmp Voice2Code Voice3 ; voice bank 3 nop SelectBank4 jmp Voice3Code ENDM MAC JUMP_TABLE_VB_K ; start of Vertical Blank and Kernel banks RORG $F000 SystemStart ; inititialize system nop SelectBank1 jmp SystemStartCode VerticalBlank ; game logic (Vertical Blank) nop SelectBank5 jmp VBCode Overscan nop SelectBank1 jmp OverscanCode IntroKernels ; kernels nop SelectBank6 jmp IntroKernelsCode Kernels3 ; kernels nop SelectBank7 jmp Kernels3Code Kernels4 ; kernels nop SelectBank8 jmp Kernels4Code ENDM 1 Quote Link to comment Share on other sites More sharing options...
Just Jeff Posted December 21, 2018 Author Share Posted December 21, 2018 Hmm.. That would certainly help. Thanks! I went on a nice long run and thought this over again and partially reversed my conclusion. It seems to me that BANKS_AND_VECTORS is unchangeable- so I get that. But, with JUMP_TABLE for example, if Bank 3 didn't use the JUMP_TABLE macro, and only had: SystemStart ; inititialize system nop SelectBank1 jmp SystemStartCode MCP ; game logic nop SelectBank1 jmp MCPCode Overscan nop SelectBank1 jmp OverscanCode IntroKernels ; kernels nop SelectBank2 jmp IntroKernelsCode Kernels3 ; kernels nop SelectBank3 jmp Kernels3Code and I left the rest of the banks off, then you could always jump to it. And if that bank only needed to jump to bank one, its covered there too- right? Additionally, if I had 16 banks, then bank 16, for example, could have something like ORG $F000 ;????? SUBROUTINE: ; insert any subroutine here rts ; ORG $F0?? ; Wherever the macro has it Bank16 nop SelectBank16 jmp SelectBank16Code ; a larger subroutine could jump to here then rts I'm still a little weak on ORGs and RORGs nor do I know exactly what address Bank 16 is in the macro. Does this work? Quote Link to comment Share on other sites More sharing options...
Just Jeff Posted July 7, 2019 Author Share Posted July 7, 2019 (edited) On 12/10/2018 at 10:21 AM, SpiceWare said: EF - has sixteen 4K banks. Uses $1FE0 - $1FEF to select bank, so would need to adjust the BANKS_AND_VECTORS. I'm having trouble getting this one to work. Would it look like this? Also, it looks like it wastes 12 bytes between the last hot spot and the reset vector (So I added a RORG): MAC BANKS_AND_VECTORS ; end of every bank RORG $1FE0 ;WAS RORG $FFF4 SelectBank0 .byte $00 SelectBank1 .byte $00 SelectBank2 .byte $00 SelectBank3 .byte $00 SelectBank4 .byte $00 SelectBank5 .byte $00 SelectBank6 .byte $00 SelectBank7 .byte $00 SelectBank8 .byte $00 SelectBank9 .byte $00 SelectBank10 .byte $00 SelectBank11 .byte $00 SelectBank12 .byte $00 SelectBank13 .byte $00 SelectBank14 .byte $00 SelectBank15 .byte $00 ; .word SystemStart ; NMI used for banks 7 and 8 RORG $1FFC ;Added because there is blank space. .word SystemStart ; RESET .word SystemStart ; IRQ ENDM Edited July 7, 2019 by BNE Jeff Quote Link to comment Share on other sites More sharing options...
+SpiceWare Posted July 7, 2019 Share Posted July 7, 2019 Provided your cartridge ROM starts with RORG $1000, then that looks like it should work. Quote Link to comment Share on other sites More sharing options...
Just Jeff Posted July 8, 2019 Author Share Posted July 8, 2019 14 hours ago, SpiceWare said: Provided your cartridge ROM starts with RORG $1000, then that looks like it should work. The jump table- right? MAC JUMP_TABLE ; start of every bank RORG $1000 And my 16 banks will ORG $0000, $1000, $2000, … F000- right? Does the bank with ORG $1000 need to be the one that contains my SystemStart (@ the reset vector)? Quote Link to comment Share on other sites More sharing options...
Nukey Shay Posted July 8, 2019 Share Posted July 8, 2019 The bank that the SystemStart exists in is ALL of them. The important thing is whether all banks can reach the "cold start routine" that SystemStart banks to when the 2600 is powered up (bank status is unknown at powerup). Make sure that the address specified by the reset vector ($xFFC and $xFFD) in every bank is indicating the SystemStart address (using the above method, the code that the macro generates needs to exist at the same location in every bank). Have you tried letting Dasm generate a list when you assemble? Use the L switch -l followed by a text file name. You can check that to see if the macro code and system vectors are being placed correctly. If you are unsure, post one. 1 Quote Link to comment Share on other sites More sharing options...
+SpiceWare Posted July 8, 2019 Share Posted July 8, 2019 Yes, the jump table. Looking at the comments: Cartridge class used for Homestar Runner by Paul Slocum. There are 16 4K banks (total of 64K ROM). it looks like there's only the one game that used it, so auto-detect might not recognize your ROM. Hit ALT-L or COMMAND-L developer key in Stella to see what it IDed the bankswitch type as, for Asteroids it detects F8. The * means autodetected. If you need to override it then load your game in Stella and: hit TAB click on Game Properties... click the Type dropdown select EF click OK click Close reload your game 1 Quote Link to comment Share on other sites More sharing options...
+SpiceWare Posted July 8, 2019 Share Posted July 8, 2019 Looking at function isProbablyEF in CartDetector I see: // Newer EF carts store strings 'EFEF' and 'EFSC' starting at address $FFF8 // This signature is attributed to "RevEng" of AtariAge I did a quick search but didn't find where @RevEng has done that, maybe this ping will cause him to chime in with a link to his post about this. Quote Link to comment Share on other sites More sharing options...
RevEng Posted July 8, 2019 Share Posted July 8, 2019 Not sure what the ask is here, but the EFEF/EFSC footer detection was added to stella when I added 64k support to bB. This is the relevant bits from the bB footer... if bankswitch == 64 ORG $10FF0 RORG $1FFF0 lda $ffe0 ; we use wasted space to assist stella with EF format auto-detection ORG $10FF8 RORG $1FFF8 ifconst superchip .byte "E","F","S","C" else .byte "E","F","E","F" endif 1 Quote Link to comment Share on other sites More sharing options...
Just Jeff Posted July 8, 2019 Author Share Posted July 8, 2019 10 hours ago, Nukey Shay said: The bank that the SystemStart exists in is ALL of them. The important thing is whether all banks can reach the "cold start routine" that SystemStart banks to when the 2600 is powered up (bank status is unknown at powerup). Make sure that the address specified by the reset vector ($xFFC and $xFFD) in every bank is indicating the SystemStart address (using the above method, the code that the macro generates needs to exist at the same location in every bank). Have you tried letting Dasm generate a list when you assemble? Use the L switch -l followed by a text file name. You can check that to see if the macro code and system vectors are being placed correctly. If you are unsure, post one. Thanks.. I see a problem in the list file.. As noted before, the bankswitch addresses end 16 bytes before the end of the ROM space (why? I don't know). To place the reset and IRQ vectors in the right place, I added a second RORG to the macro. Its being ignored. ORG $FFFC is not being generated by RORG $1FFC. This is the case on all of the banks. 177 ffe0 ORG $FFE0 0 ffe0 BANKS_AND_VECTORS 1 ffe0 RORG $1FE0 2 ffe0 3 ffe0 00 SelectBank0 .byte.b $00 4 ffe1 00 SelectBank1 .byte.b $00 5 ffe2 00 SelectBank2 .byte.b $00 6 ffe3 00 SelectBank3 .byte.b $00 7 ffe4 00 SelectBank4 .byte.b $00 8 ffe5 00 SelectBank5 .byte.b $00 9 ffe6 00 SelectBank6 .byte.b $00 10 ffe7 00 SelectBank7 .byte.b $00 11 ffe8 00 SelectBank8 .byte.b $00 12 ffe9 00 SelectBank9 .byte.b $00 13 ffea 00 SelectBank10 .byte.b $00 14 ffeb 00 SelectBank11 .byte.b $00 15 ffec 00 SelectBank12 .byte.b $00 16 ffed 00 SelectBank13 .byte.b $00 17 ffee 00 SelectBank14 .byte.b $00 18 ffef 00 SelectBank15 .byte.b $00 19 fff0 20 fff0 RORG $1FFC 21 fff0 00 10 .word.w SystemStart 22 fff2 00 10 .word.w SystemStart 179 fff4 The macro code: MAC BANKS_AND_VECTORS ; end of every bank RORG $1FE0 ;WAS RORG $FFF4 SelectBank0 .byte $00 SelectBank1 .byte $00 SelectBank2 .byte $00 SelectBank3 .byte $00 SelectBank4 .byte $00 SelectBank5 .byte $00 SelectBank6 .byte $00 SelectBank7 .byte $00 SelectBank8 .byte $00 SelectBank9 .byte $00 SelectBank10 .byte $00 SelectBank11 .byte $00 SelectBank12 .byte $00 SelectBank13 .byte $00 SelectBank14 .byte $00 SelectBank15 .byte $00 RORG $1FFC ;Added because there is blank space. .word SystemStart ; RESET .word SystemStart ; IRQ ENDM What am I doing wrong there? I do see that my old RORG reflected a 64K ROM space with $FFF4 (even though it was a 32K game), I'm only reflecting 4K here with $1FFC- does that matter? Quote Link to comment Share on other sites More sharing options...
RevEng Posted July 8, 2019 Share Posted July 8, 2019 3 minutes ago, BNE Jeff said: ORG $FFFC is not being generated by RORG $1FFC. RORG won't generate an ORG statement on it's own. Dasm has no idea about the 2600 memory space. You need to pair the ORG with an appropriate RORG yourself. Quote Link to comment Share on other sites More sharing options...
Just Jeff Posted July 8, 2019 Author Share Posted July 8, 2019 8 hours ago, SpiceWare said: Yes, the jump table. Looking at the comments: Cartridge class used for Homestar Runner by Paul Slocum. There are 16 4K banks (total of 64K ROM). it looks like there's only the one game that used it, so auto-detect might not recognize your ROM. Hit ALT-L or COMMAND-L developer key in Stella to see what it IDed the bankswitch type as, for Asteroids it detects F8. The * means autodetected. If you need to override it then load your game in Stella and: hit TAB click on Game Properties... click the Type dropdown select EF click OK click Close reload your game Thanks.. I was able to switch using this. It was generally identifying the ROM as 4K although for some of my attempts, it thought it was a 64K Megaboy. Quote Link to comment Share on other sites More sharing options...
+SpiceWare Posted July 8, 2019 Share Posted July 8, 2019 11 minutes ago, BNE Jeff said: Thanks.. I was able to switch using this. It was generally identifying the ROM as 4K although for some of my attempts, it thought it was a 64K Megaboy. Did that fix the problem? If so change this: RORG $1FFC ;Added because there is blank space. .word SystemStart ; RESET .word SystemStart ; IRQ to this: RORG $1FF8 .byte "E","F","E","F" .word SystemStart ; RESET .word SystemStart ; IRQ and Stella should autodetect EF bankswitching. Quote Link to comment Share on other sites More sharing options...
Just Jeff Posted July 8, 2019 Author Share Posted July 8, 2019 (edited) 30 minutes ago, RevEng said: RORG won't generate an ORG statement on it's own. Dasm has no idea about the 2600 memory space. You need to pair the ORG with an appropriate RORG yourself. Dang it! Thanks for the help everybody. I stuck 12 bytes in the macro as a spacer. 64K EF autodetected: Edited July 8, 2019 by BNE Jeff 1 Quote Link to comment Share on other sites More sharing options...
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