GTROM/Cheapocabra mapper for PowerPak

GTROM/Cheapocabra mapper for PowerPak
by NovaSquirrel on 2017-10-28 (#206883)

I added support for GTROM to the PowerPak. It supports everything except the LEDs and the self-flashing.

Not super useful because there's no public ROMs that I know of, and developers already have development boards. I made it because I saw someone offer to playtest someone else's game via PowerPak, and couldn't.

Re: GTROM/Cheapocabra mapper for PowerPak
by tokumaru on 2017-10-28 (#206886)

That's cool! A while ago I wanted to do play with the extra VRAM, but ended up not doing it due to lack of support for the mapper. What's the state of emulator support of GTROM these days?

Re: GTROM/Cheapocabra mapper for PowerPak
by NovaSquirrel on 2017-10-28 (#206888)

There's a custom version of FCEUX that supports it, and I heard there was a Nintendulator implementation, but it's not in the official download either.

The FCEUX version lacks the $3000-$3eff PPU RAM, which my mapper has.

Re: GTROM/Cheapocabra mapper for PowerPak
by FrankenGraphics on 2017-10-28 (#206901)

That's really cool! Like you said, i've got a test cart, but you never know when you might need this. Also, i think it might be quicker to test via PowerPak.

Quote:

Not super useful because there's no public ROMs that I know of

It might be useful because of the same. With spotty emulator support + the fact that physical carts always will cost at least something leans in favor of commercial releases. PowerPak support might be a way to make demos, examples and other public works viable.

Re: GTROM/Cheapocabra mapper for PowerPak
by Memblers on 2017-10-30 (#207060)

Thanks for making that, Nova, it is greatly appreciated.

I've attached the full version of the test program, if anyone wants that. It self-destructs with a full chip erase, so only run it on a real GTROM if you have the external programmer (the customized Game Genie), because it will only work once!

FrankenGraphics wrote:

Also, i think it might be quicker to test via PowerPak.

Definitely, as writing flash takes much longer than writing RAM. At one point I had considered building a few SRAM versions of GTROM for dev use, but thankfully this PowerPak mapper makes that idea redundant. The USB to NES adapter may be used with the pc2nes program by thefox http://forums.nesdev.com/viewtopic.php?t=7520
With that, I'm getting about 10kb/sec, which is about 8 times faster than my (unoptimized) flash loader. When uploading 512kb, 256kb, that time difference adds up fast. Note that pc2nes uploads the 40kB+ mapper file as well as the ROM.

Re: GTROM/Cheapocabra mapper for PowerPak
by Broke Studio on 2019-05-13 (#238772)

Everdrive N8 support here : http://forums.nesdev.com/viewtopic.php?f=9&t=18841

Re: GTROM/Cheapocabra mapper for PowerPak
by Broke Studio on 2019-05-14 (#238814)

What is the difference between "gtrom-ram-test.nes" provided by NovaSquirrel and "gtrom-flash-ram-test.nes" provided by Memblers ?
The first seems to work fine with my Everdrive mapper, but not the 2nd one.

Re: GTROM/Cheapocabra mapper for PowerPak
by lidnariq on 2019-05-14 (#238842)

If nothing else, Memblers's test ROM

Quote:

self-destructs with a full chip erase

, i.e. it requires functional self-flashing support.

Re: GTROM/Cheapocabra mapper for PowerPak
by Memblers on 2019-05-14 (#238848)

The flash test does the full chip erase, writes LFSR data to (some of) the FlashROM in every bank, resets the LFSR seed, then verifies. If you have a UART on the controller port, set to 19200 8N1, you'll see this output during the test:

Code:

UUUUªªªªªªCHR-RAM OK
Cheapocabra Programmer and Diagnostics V2.0 - Flash and RAM test
PRG Erased
Blank checking...
PRG Blank Check OK
Running CHR tests...
Running CHR tests...
$8000 PRG Page #0 45 23 01 26
$8000 PRG Page #1 50 8C 6E B0
$8000 PRG Page #2 ED E4 31 7A
$8000 PRG Page #3 D6 06 81 71
$8000 PRG Page #4 3B 13 18 07
$8000 PRG Page #5 2A 78 E4 1E
$8000 PRG Page #6 12 0E 7A 61
$8000 PRG Page #7 C1 8E 56 A7
$8000 PRG Page #8 D5 17 3A 16
$8000 PRG Page #9 AB 40 E6 22
$8000 PRG Page #A E8 7D 21 C0
$8000 PRG Page #B 3A 6F 61 2F
$8000 PRG Page #C 39 97 0C 4F
$8000 PRG Page #D 30 7B 85 62
$8000 PRG Page #E 20 78 BD 46
$8000 PRG Page #F 89 6E 48 27
$8000 PRG Page #0 45 23 01 26
$8000 PRG Page #1 50 8C 6E B0
$8000 PRG Page #2 ED E4 31 7A
$8000 PRG Page #3 D6 06 81 71
$8000 PRG Page #4 3B 13 18 07
$8000 PRG Page #5 2A 78 E4 1E
$8000 PRG Page #6 12 0E 7A 61
$8000 PRG Page #7 C1 8E 56 A7
$8000 PRG Page #8 D5 17 3A 16
$8000 PRG Page #9 AB 40 E6 22
$8000 PRG Page #A E8 7D 21 C0
$8000 PRG Page #B 3A 6F 61 2F
$8000 PRG Page #C 39 97 0C 4F
$8000 PRG Page #D 30 7B 85 62
$8000 PRG Page #E 20 78 BD 46
$8000 PRG Page #F 89 6E 48 27
Flash and PRG Banking OK

In the RAM-only test, I think I just commented all out the Flash-related parts.