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TI Calc and Bank Switching on the UberGROM

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I'm trying to get TI Calc working on the UberGROM. 

 

One GROM3 6K GROM, and a 32K Bank Switched ROM. I programmed the GROM3 easily enough into the UberGROM.  I concatenated the 32K ROM over and over to reach 512K for the ROM portion.  I've attached what I have been working off of.

 

I can select English, see a quick TI Calc green title screen, and then I get garbage after I launch.    Can someone please check a proper known dump of TI Calc and verify against mine?  

 

Thanks!

 

 

 

TI-CALC.zip

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26 minutes ago, mizapf said:

Also here, did you check the MAME zip file? I spent quite some time to verify the integrity of the cartridges.

 

The MAME zip is very likely correct, since the CRC16 sums match.

 

http://ftp.whtech.com/Cartridges/MAME/zip/ticalc.zip

 

 

I think the MAME cart might be missing two banks of the ROM.  It was 4 banks ROM.

 

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Flottman's version worked - after I reversed the four 8K banks, and then copied that 32K block sixteen times to fill the 512K ROM chip.

 

I now have a working cartridge.  Thank you!!!

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Oh, thanks for noticing me. The included ROMs are correct, but it was not clear that ROMs were missing. I tried it with the two ROMs, but nothing seemed missing.

 

How are the ROMs of that image arranged? TCR0 and TCR1 seem to be clipped (less than 8192+4 bytes).

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TI-CALC.zip

 

Here you go.  I attached the four proper ROMs and the GROM.  I also attached the UberGROM ROM (where I reversed the four banks and then concatenated them over and over into a 512K rom).

 

If the four ROMs aren't in the correct order for the bank sswitching scheme, the cart won't work.

 

ticalc_rom_ubergrom.bin

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Does anyone know for sure if the cartridges TI Calc and TI Planner are actually the same program except one was released in the U. S. and the other was released in Europe?

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14 hours ago, Flottmann1 said:

Completely different programs.

 

TI Calc is much larger.  Planner is one ROM.  TI Calc is 32K ROM + 8K GROM.

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18 hours ago, mizapf said:

But only the GROM and rom-2 have valid CRCs. Did you "fix" the other ROMs?

 

All I did to properly "format" these for programing the Ubergrom is:

1) Separate ROM images into 8192 byte images

2) Separate GROM into 6144 byte images

3) If the image was less than 8192 or 6144, I padded to 8192 or 6144

4) I then concatenate the ROM images (.C times 64, .C+.D times 32, or .C+.D+.E+.F times 16) to fill the whole 512K ROM

 

I then:

5) Program the 512K ROM on my EPROM Programmer

6) Program the 1284P on my EPROM Programmer with the vanilla GROMSIM image

7) Put the GROM 6K files on my USB Flash drive .HFE image via TIImage Tool.

8]  Move the USB Flash Drive to my /4A GoTek

9) Program the GROM 6K files (G3/G4/G5/G6/G7 from my /4A to the 1284 with GROMCfg

10) Reboot, and the cart works

 

Otherwise, the images are the same exact ones that Flottman gave me, this is attached.

 

TI-CALC.rar

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I'm in contact with Flottmann1 to get a genuine dump; he showed me a photograph. It seems as if there is one GROM and two EPROMs. TI used their internal "CD" nomenclature, but I would guess the EPROMs are 16K each, judging from the dump size.

 

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On 26 March 2020 at 3:36 PM, mizapf said:

Also here, did you check the MAME zip file? I spent quite some time to verify the integrity of the cartridges.

... since the CRC16 sums match.

 

 

I thought it was CRC-CCITT.  I could be confusing it with CRC's used by Xmodem-CRC or disk controllers.  CRC16 and CRC-CCITT are both 16-bit.

 

First post and I hijack a thread.

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One note on TI-Planner. There are two names for it. It was originally released as Console Calc, but at some point DataBioTics changed the name to TI Planner. They did this with a number of their cartridges--probably in an attempt to make and older program fresh and new in consumer eyes.

 

As already seen, it has no relation to the TI Calc cartridge from TI (or for that matter, to the TI Calc cassette program that was released as one of the SAMS titles in the US).

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Guys, everything is fine, I finally remembered how. I added the special TICALC decoding to MAME after I found out how it works.

 

    ROM space
    6000                    7000                 7fff
    |                        |                     |
    |                        |===== ROM bank 0 ====|       write to 7000
    |                        |                     |
    |=== ROM bank 0 =========|===== ROM bank 1 ====|       write to 7002
                             |                     |
                             |===== ROM bank 2 ====|       write to 7004
                             |                     |
                             |===== ROM bank 3 ====|       write to 7006

    This is very similar to the MBX scheme, only that the bank switch is
    done by writing to the first words of the 7000 space. Also, there is no
    additional RAM.

 

These ROMs are 8K each, so we have 16K ROM space. Still, we have four banks of 8K. How does that match? - You see it in the above drawing (taken from my implementation).

 

ROM1 hosts bank 0 and bank 1, ROM2 hosts bank 2 and bank 3. Bank 0 appears in 6000-6FFF, and by writing to 7000/7002/7004/7006, you map bank 0,1,2,3 to 7000-7FFF.

 

Accordingly, in MAME, I glued together bank 0 and bank 1 into one 8K image, and bank 2 and bank 3 into another 8K image. I have a good indication (maybe we could dare to say a proof) that this is correct: At the end of the bank 1 image there is a CRC16 value, and it matches the contents of the concatenated banks 0 and 1. Same holds for bank 3, with respect to bank 2 + bank 3.

 

This is what you would get when you read out the ROMs externally.

 

This also means that the MAME dumps cannot be used in HSGPL or UberGROM. You'd have to "unfold" the ROMs again to make 4*8K.

 

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3 hours ago, mizapf said:

 

This also means that the MAME dumps cannot be used in HSGPL or UberGROM. You'd have to "unfold" the ROMs again to make 4*8K.

 

Correct.  There's no "partial bank switching" - we bank the whole 8K segment.  So, if you want to repeat the first 4K, simply just repeat the ROM with the first 4K in each of the four "banks".

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