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Does Anyone Own a Gundhara PCB?

twistedsymphony

twistedsymphony

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I'm hoping someone here own an original Gundhara PCB that can help me with some component part numbers and maybe take some photos for me.

Primarily I'm trying to find what ICs are used on U2-1, U2-1, U5-1, and U5-2 (the SMD RAM chips on the back edge of the PCB)
 
Sure can.

They are NEC D43256AGU-10L & D43256AGU-12L.
Pic :
IMG_7301.jpg
(yeah my Gundhara board is in not so great condition - looks like a cap has leaked on it from another board maybe ?)
 
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So I own this Zombie Raid pcb and I see that Gundhara would be a much better game. Anyone ever did a conversion? there are differences in the board but a LOT of exactly the same thing!

thanks to @caius repair for this Gundhara picture:
Gundhara_PCB_800.jpg


and my zombie raid:
3CFA93C8-5582-4763-A6BC-520C05418A5B.jpeg
 
AlxUnderBase said:
Even if the hardware isnt 100% the same ? (ive noticed some differences in logics side , in the top of pcb
Click to expand...
I started working on this years ago (this thread was created while I was looking into it). it's stuck and can't progress further without those PALs though.

I have several other conversions on this hardware that have progressed a way, also stuck due to not having PALs.
 
twistedsymphony said:
not possible without the PAL Dumps from Gundhara.
Click to expand...

ok ... so for gundhara AND Zombie Raid, MAME list the pals as :


ROM_REGION( 0xc00, "plds", 0 )
ROM_LOAD( "fx-001.u206", 0x000, 0x104, NO_DUMP )
ROM_LOAD( "fx-002.u116", 0x200, 0x104, NO_DUMP )
ROM_LOAD( "fx-003.u14", 0x400, 0x104, NO_DUMP )
ROM_LOAD( "fx-004.u35", 0x600, 0x104, NO_DUMP )
ROM_LOAD( "fx-005.u36", 0x800, 0x104, NO_DUMP )
ROM_LOAD( "fx-006.u76", 0xa00, 0x104, NO_DUMP )


ROM_REGION( 0xc00, "plds", 0 )
ROM_LOAD( "fy-001.u206", 0x000, 0x104, NO_DUMP )
ROM_LOAD( "fy-002.u116", 0x200, 0x104, NO_DUMP )
ROM_LOAD( "fy-003.u14", 0x400, 0x104, NO_DUMP )
ROM_LOAD( "fy-004.u35", 0x600, 0x104, NO_DUMP )
ROM_LOAD( "fy-005.u36", 0x800, 0x104, NO_DUMP )
ROM_LOAD( "fy-006.u76", 0xa00, 0x104, NO_DUMP )

So are they the same or are they just at the same location? we don't know cause they are not dumped? :D
dumping them is probably not trivial and not something that I can do but is there anything that my zombie raid board can help with? if so, who could do it?
 
So I've recently picked this back up again.
I've dumped some of the PLDs on Zombie Raid and dug into the code on them to understand what they're doing. https://wiki.pldarchive.co.uk/index.php?title=Zombie_Raid

I've found that a BIG part of this platform is the jumper configuration (you'll notice a lot of 3 points surrounded by a box and labeled ABC, or similar throughout the boards. These are the jumpers and they're unique per game.

Anyone with a Gundhara PCB able to get clear pictures of each of these jumpers on BOTH sides of PCB? @parodius is this something you can get? also the photo of the RAM chips seems to have disappeared so if you could re-post that, that'd be awesome.

Also trying to understand the RAM differences on these two games I've found data sheets on the NEC chips used by Gundhara and by Zombie Raid, but I can't find one for the Hitachi HM9253101FPT used on Zombie Raid... if anyone can found a datasheet for that it would be helpful.

Another tricky part of this conversion will likely be the audio, Zombie Raid uses a weird audio setup and the analog controls seem to be mapped to where other games use the audio system interrupt, so we'll need to figure that out... but RAM and jumpers first!
 
mapping out the RAM section on Zombie Raid....
U5-2 seems to be populated on SOME PCBs but not others, and U2-2 seems to be not populated on any of them.

Here is how they map out:
ZR_SRAM.jpg


Green is what I expected to see, orange and red is NOT what I expected to see, and are the pins I suspect may differ from Gundhara.
I should also mention that Vcc is connected to 5V on all but U5-2, which is connected to the battery Diodes instead.

I think U2-2 Pin 20 (CS) should probably be U14 Pin 16 instead (like U5-2) and I'd expect Pin 26 (A13) of U5-2 to connect to Pin 26 on all of the other RAM chips.

We'll need someone who owns a Gundhara and a multi-meter to check this out to see if my assumptions are correct.


--------------------------------
UPDATE:

poking around a bit more and looking at the MAME Driver there's this in the address MAP:
Code: 
	map(0x200000, 0x20ffff).ram();                             // RAM
	map(0x210000, 0x21ffff).ram();                             // RAM (gundhara)
	map(0x300000, 0x30ffff).ram().share("nvram");              // actually 8K x8 SRAM in zombraid
So main RAM is at 0x200000
Then it lists extra RAM for Gundhara at 0x210000
then it lists Zombie Raid SRAM at 0x300000

So the chips U5-1 and U2-1 appear to be the Main RAM at 0x200000, they're the right size and they're enabled by the PAL at U14 Pin 17, which activates in the 0x2_____ memory range
So the chip at U5-2 that is equipped on SOME Zombie Raids is an 8K x8 SRAM and it's enabled by the PAL at U14 Pin 16, which activates in the 0x3_____ memory range

looking at U2-2 (unpopulated on zombraid) it's activated by the demultiplexer at U232. this is activated by PAL U14 Pin 17 (so the 0x2_____ range) and demultiplexes A17 and A16 so that it activates at 0x21____ So it seems that U2-2

that makes the updated chart look like this:

ZR_SRAM_v2.jpg


so I think U2-2 is complete and correct. the OE pin is "probably" correct and should be confirmed. but it does call into question the OE of U5-1 and U2-1 as they'll be always be enabled at the same time as U2-2... they should probably have their OE pin tied to U232, maybe Pin 12?

it'd be nice to have confirmation from an original PCB owner before I go cutting traces and lifting pins to see if my analysis is correct lol
 
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So while I wait for confirmation on the RAM pins I started poking at some other stuff.. it seems that the Sprite ROMs are configured differently here as well.

Weirdly other games on similar hardware (like Blandia) have the Sprite ROMs organized in pairs of 2 to make 32-bit data but Zombie Raid only uses a single ROM. I've confirmed that ROMs U64, U63, and U201 are permanently disabled on Zombie Raid, and U200 is permanently enabled, further the logic for bank switching between U63/U64 and U201/U202 is missing from Zombie Raid also. Zombie Raid also has a pair of flipflops mixed in here as well and I'm unsure what they're actually doing.

making this work will require some re-wiring. It may also be possible to take another board (like Blandia) and double the RAM (that seems to be the biggest difference between Gundhara and other games). Not sure what would be the easiest path at this point.
 
plasticfactory said:
What exactly are you still needing from a PCB owner? I have a Gundhara and can take some pictures or poke around, if it would be helpful.
Click to expand...
Here's my check list:
1. Check that U5-2 Pin 26 is connected to U2-2 Pin 26 (and also to U2-1 Pin 26 and U5-1 Pin 26)
2. Check that U5-1 and U2-1 Pin 20 are connected to U232 Pin 12
3. Check that U232 Pin 12 is NOT connected to U232 Pin 15
4. Check that U5-2 Pin 20 is Connected to U2-2 Pin 20, and also connected to U232 Pin 11
5. Check that U63 Pin 11 and U64 Pin 11 are connected to U62 Pin 5, and also to U231 Pin 3
6. Check that U200 and U201 Pin 11 are connected to U231 Pin 4

The above are my assumptions of what they SHOULD be on Gundhara, which is different than what they are on the Zombie Raid hardware

I'm sure there is other stuff I'll need checked but this should confirm my assumptions about the RAM and the Sprite ROM differences.
 
If anyone who owns one of these and is willing to sell it, I'd be happy to buy it and have it sent direct to TS so he can get his work done on this. I think it would help a lot in the community both fix and possibly convert to play this game.

The offer is there and I'll pay going rate!
 
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