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  1. It may be interesting to capture the states right after reset goes high for further insight. The 6502 takes 7 cycles to reset as it follows the same sequence as an interrupt, but slightly modified in that it has dummy read accesses to the stack. If the CPU is sane, right out of reset you should see a sequence stack read accesses at 00FF, 0100, 01FF, and 01FE right before the reset vector pull at FFFC. Then you'll know if you're really coming out of reset and pulling the right address from ROM at the reset vector.
  2. I suspect the MMU, but you’re going to need some other tools (hardware and software) besides a continuity test to validate this. There’s nothing particularly special about the MMU, it’s simply an address decoder with lots of inputs and all logic equations are known. People like to throw shade on the built-in self test as the RAM tester isn’t particularly rigorous, but at the very least it will checksum the OS. So if your self test shows green on both ROM blocks, you can reasonably assume your OS chip is OK. If it fails, it can be the MMU or the OS chip. I'm going to assume it's not the OS because you can jump into BASIC. If you have a device programmer you can make your own MMU with a GAL or a PAL16L8. If you examine the schematic of the cartridge slot and the logic associated with it, the relevant pins to focus on the MMU are 7, 8, 12, and 19. Pins 7 and 8 are the “ROM Detect” lines that disable the onboard RAM when there is an 8K block of ROM present. These are pins pulled high on the cartridge PCB to change the memory topology depending on whether it needs an 8K or 16K hole in the address space. RD4 (pin 7) and RD5 (pin disable the system RAM at $8000-$9FFF and $A000-$BFFF, respectively, and also enable the active-low ROM chip selects S4- (pin 19) and S5- (pin 12) for cartridge. They both have pull-down resistors to ground in their normal (no cartridge) state. Step one is to see if the RD lines are working from the cart slot to the MMU pins. I’m assuming you know how to use a voltage meter or better yet, have a logic probe. No cartridge: pin 7 low, pin 8 low Star Raiders: pin 7 low, pin 8 high Pole Position: pin 7 high, pin 8 high If you don’t see those logic levels on the MMU pins, you have either have an internal short in the MMU or a bad connection from the cart PCB <-> cart slot <-> MMU. To isolate the MMU, simply remove it from the socket and test those same pins without it present. If don’t you see those levels without the MMU in the socket (the machine obviously won’t work), then you have a physical connection issue. Otherwise, if you see the right levels with the MMU removed, then the MMU is at fault. Step two is to see if the ROM selects are actually triggering. With Star Raiders, you should see activity on pin 12. You have a use a logic probe or oscilloscope for that, as the transitions will be too fast to register a voltage meter. If you don’t see pulsing on pin 12 after you push reset, then the MMU is most likely bad or there is a connection issue (or the cart is toast, but you've tried too many). Alternatively, if the machine is otherwise working and you have a way to boot something, I’ve used a tool called DEBUG+ for years that I modified to load into low memory (by default it loads into $A100, which obviously won’t work with a cartridge inserted so the custom version loads into $2100). You can actually use whatever tool you want really, as long as it doesn’t load into the cartridge area. The premise here is you want to examine the memory to trigger accesses to the cartridge address space and see if there are pulses on pin 19 for $8000-$9FFF, or pin 12 for $A000-$BFFF. The pulses will only be present in those ranges if the corresponding RD line is high. The benefit of using a memory debugging tool like this is you can also see if there is valid data when the ROM is enabled, so you could also conceivably diagnose a data bus or address bus fault if you know what is supposed to be there. If the selects aren't enabling the ROM, the bus will float and you’ll see data values corresponding to the upper address byte that will change when you cross a page boundary. What this looks like can be simulated by pulling the ROM chips on a cartridge. The moral of the story is: troubleshoot before shotgunning chips. I’ve got a stack of arcade boards I’ve repaired where previous owners replaced dozens of chips but completely missed the blatantly obvious problem that would have made it a ridiculously simple repair (along time and money saved) had they spent 5-10 minutes with a logic probe in a critical area.
  3. Thanks for trusting me to be your hands and eyes on the other side of the world to get this to you. Once I started unpacking and sorting through things to strategize how to best pack everything, it became apparent how special and one-of-a-kind this collection is. This was/is a substantial investment in software. I saw many titles I recognized but this was dwarfed by many more I didn't (some of them new in original shrink wrap, completely unaware they were now in the 21st century), as well as an extravaganza of cassettes. It was truly like stepping into a time machine and being transported back to that golden era. There are some real gems in this lot. On a comical note, this shipment of four boxes made quite a commotion at the UPS store. Apparently the clerk normally only deals with small domestic packages and packing up cable modems to ship back to their providers. This was the most expensive international shipment that he had ever handled and was affirmed with gasps of astonishment and curiosity from the other patrons behind me at the total cost (this weighed a little over 160 lbs) and the contents of these boxes that would warrant such an expense. While working my way through the stack of customs forms and singing away, it was reminiscent of applying for a large loan. The best was the amusingly sardonic exchange with the clerk that went something like this through out this long process: UPS Clerk: OK, I need to know... No. Sorry. CUSTOMS needs to know what is in these boxes Me: Old computer stuff UPS Clerk: Old computers? They don't have old computers in France?!? Me: This is a special collection that is 30-40 years old. UPS Clerk: No idea why someone would want to use a computer that old today, but we will make sure it gets to France; sign and initial here. Lesson learned: If you're shipping something UPS, especially internationally, beware of using their website to estimate the cost. I had exact dimensions and weight and it still provided a rather under-valued total when done in person.
  4. Also in Houston in the Clear Lake area.
  5. I ordered an FD1797 from here a few years ago, don't know if they still have any: https://www.unicornelectronics.com/IC/CRT.html U46 is a bi-polar PROM that loads the counter for the data separator and it does run hot.
  6. Not 6502, but close. It is 6800 (or close derivative). I’m using the 01 file. Look at the last eight bytes. There’s four big-endian addresses. The reset vector goes to $F259, the NMI vector goes to $E4C1. In 6800-speak at $F259 you have: 1251 C1 AA cmpb #$AA 1253 27 03 beq $1258 1255 73 00 1C com $001C 1258 39 rts 1259 0F sei 125A 8E 00 7E lds #$007E 125D 86 66 ldaa #$66 125F B7 40 00 staa $4000 1262 CE 00 00 ldx #$0000 1265 86 AA ldaa #$AA 1267 A7 00 staa $00,x 1269 E6 00 ldab $00,x 126B 11 cba 126C 26 C3 bne $1231 126E 43 coma 126F 2A F6 bpl $1267 1271 6F 00 clr $00,x 1273 08 inx 1274 8C 00 80 cpx #$0080 1277 26 EC bne $1265 1279 86 20 ldaa #$20 127B 97 1F staa $1F 127D 86 31 ldaa #$31 127F 97 30 staa $30 1281 CE 01 A0 ldx #$01A0 1284 DF 5D stx $5D 1286 BD F2 23 jsr $F223 Looks like a valid sequence for memory test code to me, including disabling interrupts on power up. That's no coincidence. The NMI vector code at $E4C1: 04B8 86 02 ldaa #$02 04BA 8D 89 bsr $0445 04BC 8D D0 bsr $048E 04BE 8D A1 bsr $0461 04C0 39 rts 04C1 C6 57 ldab #$57 04C3 BD F1 F0 jsr $F1F0 04C6 3B rti Even terminates with an RTI, that's no coincidence either.
  7. I did some work on this a few years ago as I wanted the ability to build the 850 ROM code from the source Curt provided, but obviously the relocation code is missing. My guess is they had some helper program generate the offsets in the relocator table. This is part of the source I use with an automated build script that generates the 850 ROM in five phases (relocatable handler, handler arithmetic checksum, relocator, relocator arithmetic checksum, and main code). The only part that is missing is dynamically generating the offsets in the table (right now it is hard-coded), although some of the values I can get from the ATASM label dump. DDEVIC = $0300 DBUFLO = $0304 DBUFHI = $0305 DBYTLO = $0308 DBYTHI = $0309 DTIMLO = $0306 DUNIT = $0301 DSTATS = $0303 DCOMND = $0302 SIOV = $E459 MEMLO = $02E7 DOSINI = $000C ZPTMP = $80 ORIGIN = $0500 *= ORIGIN .BYTE 0,3 ; FLAGS, SECTOR COUNT .WORD ORIGIN ; ENTRY ADDRESS .WORD $E4C0 ; ADDRESS OF RTS INSTRUCTION IN OS !!!!!!!!!! LDA #$50 STA DDEVIC LDA MEMLO STA DBUFLO LDA MEMLO+1 STA DBUFHI ; Original 850 Handler is 1425 bytes in size LDA #< HANDLL STA DBYTLO LDA #> HANDLL STA DBYTHI STA DTIMLO LDA #$01 STA DUNIT LDA #$40 STA DSTATS LDA #$26 STA DCOMND JSR SIOV BPL RELOC SEC RTS RELOC LDX # RELOCTABLEND - RELOCTABL ADJOFFSET CLC LDA RELOCTABL-2,X ADC MEMLO STA RELOCTABL-2,X LDA RELOCTABL-1,X ADC MEMLO+1 STA RELOCTABL-1,X DEX DEX BNE ADJOFFSET LDY #$00 STY TEMP1 JSR SETADDR ; Substitute variables LOOP1 LDA (ZPTMP),Y TAX INY LDA (ZPTMP),Y PHA LDA VARTABL+1,X STA (ZPTMP),Y DEY LDA VARTABL,X STA (ZPTMP),Y PLA JSR DECADDR BNE LOOP1 LDX #$02 JSR SETADDR LOOP2 LDA (ZPTMP),Y TAX LDA VARTABL,X STA (ZPTMP),Y LDX TEMP1 INC TEMP1 LDA DELTATABL,X JSR DECADDR BNE LOOP2 LDX #$04 ; set WRMXIT JSR SETADDR LDA DOSINI STA (ZPTMP),Y INY LDA DOSINI+1 STA (ZPTMP),Y LDA RINVEC STA DOSINI LDA RINVEC+1 STA DOSINI+1 LDX #$0C ; JMP to handler start .BYTE $4C RELOCTABL .WORD $03E9 ;RINCLD VARSTART ; $05AB .word $058F ; RVECTS+4 .word $04C2 ; PREPT+2 .word $03FC ; WRMXIT+1 VARTABL .WORD $0543 ;RDVTST 0 .WORD $069C ;IOCTRL-1 2 .WORD $0694 ;PUTCTR-1 4 .WORD $0698 ;RERROR-1 6 .WORD $06BD ;ACTSTR 8 .WORD $04B4 ;PREPUT 10 .WORD $06BC ;ALLDUN 12 .WORD $06BA ;RMAINV 14 .WORD $06BB ;RMAINV+1 16 .WORD $06B4 ;RVSAVE 18 .WORD $06B3 ;OUSTAT 20 .WORD $055B ;MAKDCB 22 .WORD $06BE ;RSCHAR 24 .WORD $06A0 ;RTRANS-1 26 .WORD $00C8 ;PAROUT 28 .WORD $04F0 ;CLHIBT 30 .WORD $04D2 ;PARITY 32 .WORD $0502 ;X32M1 34 .WORD $0611 ;OUTBAS 36 .WORD $04F9 ;CIRCIN 38 .WORD $0515 ;CMP16B 40 .WORD $06AF ;NXTOUT 42 .WORD $06B0 ;NXTOUT+1 44 .WORD $06B1 ;INSTAT 46 .WORD $06B2 ;INSTAT+1 48 .WORD $0525 ;CIN16B 50 .WORD $06A4 ;RSPRCH-1 52 .WORD $06B0 ;NXTOUT+1 54 .WORD $0582 ;JMPTABL+1 56 .WORD $0581 ;JMPTABL 58 .WORD $06AB ;BOBUF 60 .WORD $06A9 ;TOBUF 62 .WORD $06AC ;BOBUF+1 64 .WORD $06AA ;TOBUF+1 66 .WORD $0536 ;CINTRY 68 .WORD $0690 ;GETCTR-1 70 .WORD $06BC ;ALLDUN 72 .WORD $058B ;RVECTS 74 .WORD $0115 ;PTBFUL 76 .WORD $04DD ;SETRNS 78 .WORD $054F ;SPCDCB 80 .WORD $0223 ;STFUNK 82 .WORD $0571 ;HANDVS 84 .WORD $0413 ;RIN 86 .WORD $06AD ;NEXTIN 88 .WORD $06AE ;NEXTIN+1 90 .WORD $050C ;INC16B 92 ; These are offsets from ORIGIN ; HANDVS table .WORD $FFFF ;RHOPEN-1 .WORD $0025 ;RHCLOS-1 .WORD $015E ;RHGET-1 .WORD $006D ;RHPUT-1 .WORD $020C ;RHSTAT-1 .WORD $0256 ;RHSPEC-1 ; JMPTBL .WORD $0370 ;FORCE-1 .WORD $0395 ;CONTRL-1 .WORD $0389 ;CONFIG-1 .WORD $039C ;TRANSL-1 .WORD $0271 ;STREAM-1 .WORD $0473 ;ROUT RINVEC .WORD $03B3 ;RINWRM .WORD $0591 ;INBASE .WORD $03FE ;RBREAK RELOCTABLEND DECADDR STA TEMP2 SEC LDA ZPTMP SBC TEMP2 STA ZPTMP BCS DECXIT DEC ZPTMP+1 DECXIT LDA TEMP2 RTS SETADDR LDA VARSTART,X STA ZPTMP LDA VARSTART+1,X STA ZPTMP+1 RTS DELTATABL ; Table at $064B - what are these? .BYTE $0A .BYTE $E6 .BYTE $05 .BYTE $85 .BYTE $0B .BYTE $48 .BYTE $05 .BYTE $37 .BYTE $05 .BYTE $00 TEMP1 .DS 1 ;$0655 TEMP2 .DS 1 ;$0656
  8. This is from my 1MB Co-Power 88 ATR_8088.ROM
  9. Thanks for the helpful suggestions, but I'll pass on releasing anything because per your criteria you didn't pay me and I'm not the creator. But don't despair. My efforts have already been disclosed to the relevant party, free of charge. However, I'm happy to take your money too so I can use it to spruce up my shitty video and release it to you in Beta format. This way you can view it in its ORIGINAL non-self-glorified professionally color calibrated splendor, in Dolby. Watch it a couple of times to understand how maybe turning your Ferenc-speak towards people that can help you down one notch can bear fruit. Because your formula obviously isn't working here. But in all seriousness, I think a good starting point for you to help fix your problem can be found here: https://www.mayoclinic.org/diseases-conditions/narcissistic-personality-disorder/symptoms-causes/syc-20366662
  10. I guess I really do know what I'm talking about. IMG_6230.m4v
  11. This is not going to work for hardware and software reasons, regardless of any settings. There are incorrect assumptions about there being missing signals on Slot 3, or other memory slots need to be populated; this is all wrong. The only thing that makes Slot 3 is unique from the other two memory slots is D5XX-, D6XX-, and EXSEL- are present. That's it, no magic there. EXSEL- disconnects the CPU databus from everything physically behind Slot 1 (personality module, PIA, carts, POKEY). On Incognito, this signal is also connected to EXTSEL- on the PBI connector. They are not the same signal or function. This signal is part of the problem. The logic needs to be modified to disable the bus in Colleen mode when this signal is asserted. That will allow the ROM to appear in the 256-byte window in $D600. Once that is addressed then the next problem is that the Bit3 firmware itself uses some memory in the stack page at $100 that it assumes is free (zero) but has Incognito code written to it when reset is pressed that wreaks havoc on the bank switching. But then again, what do I know as I was labeled a "third party" who can't possibly know anything about the internals by someone waxing poetic about the 800's super-duper architecture. 🤐
  12. Wow! That brings back some memories of late nights with a logic analyzer debugging the memory circuit on that thing. And the realization it was a miracle that it even worked with all those timing issues.
  13. I'd have to dig through my files and look at the code to see what was changed as it was quite some time ago, but I suspect it wasn't anything earth shattering between 1.4.1 and 1.4.2. I vaguely remember even regressing back to an earlier version.
  14. I'll trade you two packages of 9-count Charmin Ultra-Soft Mega rolls and 500rds of Russian 7.62x39 sealed in original wax for both.
  15. As far as the differences between the 256K and 1MB versions of the MIO, the official ICD ROMs were created from the same assembly source, with a macro defining which version to build (their comments, not mine): if ameg jsr comkey ; waste 3 bytes... 1Meg and 256K versions lda #$10 ; are not same size else lda #$04 endif This is why there is an offset between both ICD versions. My guess is they did this to obfuscate the differences to discourage folks from upgrading themselves and having them do the memory upgrade for you. The other variants you might find out there likely just have one-byte difference ($04 vs $10). All this means is someone just patched the max bank byte on the 256K version to run on a 1MB, otherwise they are identical. I know 1.2 is of ICD origin, but doesn't really have any major changes. Use at your own risk. MIO12M.128
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