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Any PGM Conversion info out there?

twistedsymphony said:
Fluffy said:
I'm not sure if the 27c322 for the audio rom will work, as the mod uses a MX29L3211 which has a 4Mx8 mode while the 27c322 is 2Mx16.
Click to expand...
That same conversion can also be done on this cart: Any PGM Conversion info out there?
which uses a 27c322 for the audio rom from the factory.

this is a newer revision of the KOVSH cart and as I said many times in this thread, this is the best template for creating a custom cart, particularly the graphics board.


I've done the conversion on one of these carts myself and it works perfectly.
Click to expand...
Ah, ok, looking closer that board uses two 74ls257 quad multiplexers to select the low and high byte, which is a better choice than wasting half the ROM space. :) Do you have any idea what the 74ls08 is doing?

By the way, I traced the M-ROM connections from the sound chip. No exciting revelations, except that (as expected) I need to add 1 to all address lines to match the chip outputs, and the highest two address bits go into the decoder.
 
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Fluffy said:
Do you have any idea what the 74ls08 is doing?
Click to expand...
Here's how it's routed:

1 - gnd
2 - gnd
3 - (nothing?)
4 - gnd
5 - gnd
6 - (nothing?)
7 - gnd
8 - U18 Pin 15 & U17 Pin 15
9 - Jumped to Pin 11
10- U12 Pin 9
11- Jumped to Pin 9
12- U12 Pin 11
13- U12 Pin 10
14- +5v
 
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twistedsymphony said:
Fluffy said:
Do you have any idea what the 74ls08 is doing?
Click to expand...
Here's how it's routed:
1 - gnd
2 - gnd
3 - ?? (nothing?)
4 - gnd
5 - gnd
6 - ?? (nothing?)
7 - gnd
8 - U18 Pin 15
9 - Pin 11
10- U12 Pin 9
11- Pin 9
12- U12 Pin 10
13- U12 Pin 9
14- +5v
Click to expand...
74ls08 is a quad AND gate, so 1-6 disables gates 1+2.

gate 3:
8: Does that go to U17 pin 15 as well? That enables the multiplexer.
9: I assume that is U1? That would be the /E line
10: is 2Y3 of the decoder
gate 4:
11: That is A1 of the ROM
12: That are 2Y2
13: and 2Y3 of the decoder

So the first gate is easy, it enables the output of the multiplexers when the ROM is enabled. The second maybe interleaves two banks? I'll have to check the mame driver tonight if there is any special handling for that board.
 
I think I typoed "10- U12 Pin 9" it goes to U12 but it definitely doesn't jump to U13 pin 13 I'll double check my notes tonight and verify with the meter.

EDIT:
ok here is the updated pinout:

1 - gnd
2 - gnd
3 - (nothing?)
4 - gnd
5 - gnd
6 - (nothing?)
7 - gnd
8 - U18 Pin 15 & U17 Pin 15
9 - Jumped to Pin 11
10- U12 Pin 9
11- Jumped to Pin 9
12- U12 Pin 11
13- U12 Pin 10
14- +5v
 
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this is as much as I could work out of U12
I couldn't trace 6 and 7 there are no visible traces to the pins, it's possible they don't go anywhere.

U12
1 - gnd
2 - edge connector (pin 27 right parts side)
3 - gnd
4 - U11 Pin 11
5 - U11 Pin 14
6 - ? unknown
7 - ? unknown
8 - gnd
-
9 - U13 Pin 10
10 - U13 Pin 13
11 - U13 Pin 12
12 - edge connector (pin 2 left solder side)
13 - edge connector (pin 15 left solder side)
14 - edge connector (pin 14 left solder side)
15 - gnd
16 - +5v
 
New version:
circuit.PNG

That makes more sense! So if O0 is selected O1-O3 will be high, which means the multiplexers will be disabled. Otherwise the output for the selected bank is low, which means one of the AND gates will output low and enable the multiplexers. As before, it is possible that O1 and O2 enable the two empty footprints and O3 is unused.

On a custom board that needs to support only one ROM you can leave out the AND gates. It is probably even possible to just use an 74ls04 inverter instead of one of the 74ls139, but that just saves 20p and you lose a bit of flexibility if you want to add a second or third M ROM bank.
 
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twistedsymphony said:
this is as much as I could work out of U12
I couldn't trace 6 and 7 there are no visible traces to the pins, it's possible they don't go anywhere.
Click to expand...
Yes, that is quite possible. That is the 2nd decoder in U12, and probably used for the two B ROMs.
U12
1 - gnd
2 - edge connector (pin 27 right parts side)
3 - gnd
4 - U11 Pin 11
5 - U11 Pin 14
6 - ? unknown
7 - ? unknown
8 - gnd
Click to expand...
Yes, that seems to be the one selecting B-ROMs, U11 is one of the level shifters. You can probably trace from the other side of it to the OE lines of the B-ROMs if you want to.
9 - U13 Pin 10
10 - U13 Pin 13
11 - U13 Pin 12
12 - edge connector (pin 2 left solder side)
13 - edge connector (pin 15 left solder side)
14 - edge connector (pin 14 left solder side)
15 - gnd
16 - +5v
Click to expand...
pin 2 left solder side (pin 61 in my schematic, and I've got the connectors on top) is probably to select a ROM on the main board.
pin 14 and pin 15 left solder side (pin 49 and pin 48 in my schematic) are MA22 and MA23, the highest two address bits from the ics 2115 sound chip.
 
By the way, are there any pictures of actual bootleg carts for pgm, or were people just converting older official carts into newer games?
 
My cheapo Ebay PGM mobo arrived today :)

Pros: New type of sound pot instead of the old dial, 2032 battery holder, board works in tests. No real cart to check with yet. No leaky battery.
Seems the plastic case is really robust, i've never seen one in real life, they look like they will withstand a lot of punishment.
I guess there are lots of these around and only a small percentage of older units will have battery damage of old age.
Cons: A little notch was broken of to make room for the sound pot on the side.

Al in all, cheap working PGM and fast shipping by DHL/Yansomething :)

Edit: Did anybody order from Sheep before and get a XX12345 GB tracking number? Everything i had tracked from China before ends in NL instead of GB, and the package shows as tracked on Heathrow UK now.. I don't get it. :(
 
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I got my Sheep Nova carts the other day.

One of my PGM motherboards I got from him has a "hiss" in the sound that is always present, even when the game is silent. Also, when the volume knob is all the way to minimum, sound/music will still be heard. Normally it should be muted at the lowest volume setting.

I have already tried to fix these problems by replacing all of the electrolytic capacitors on the PCB. No effect. Also tried cleaning the volume pot with rubbing alcohol and that didn't do anything.

Any ideas? Maybe a bad preamp chip or audio amplifier?
 
andynumbers said:
I got my Sheep Nova carts the other day.

One of my PGM motherboards I got from him has a "hiss" in the sound that is always present, even when the game is silent. Also, when the volume knob is all the way to minimum, sound/music will still be heard. Normally it should be muted at the lowest volume setting.

I have already tried to fix these problems by replacing all of the electrolytic capacitors on the PCB. No effect. Also tried cleaning the volume pot with rubbing alcohol and that didn't do anything.

Any ideas? Maybe a bad preamp chip or audio amplifier?
Click to expand...
I have a mobo with the same symptoms...
 
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It is infact, not 100% clear what is boot and what not from back in the day. Some of the "plus" stuff is seen as original, and the streetfighter / KOF hacks for some of the knights of valor games were 'difficult' to make as they should have decrypted and re-encrypted the thing, just like we run into now. But afaik nothing on special PCBs. All done on real hardware with the program code changed + gfx hacks.

All the 3 cave titles were done in the west on real hw, and it seems nowadays the east is doing them as well to catch up on sales ;)
 
Asure said:
My cheapo Ebay PGM mobo arrived today :)

Pros: New type of sound pot instead of the old dial, 2032 battery holder, board works in tests. No real cart to check with yet. No leaky battery.
Seems the plastic case is really robust, i've never seen one in real life, they look like they will withstand a lot of punishment.
I guess there are lots of these around and only a small percentage of older units will have battery damage of old age.
Cons: A little notch was broken of to make room for the sound pot on the side.

Al in all, cheap working PGM and fast shipping by DHL/Yansomething :)

Edit: Did anybody order from Sheep before and get a XX12345 GB tracking number? Everything i had tracked from China before ends in NL instead of GB, and the package shows as tracked on Heathrow UK now.. I don't get it. :(
Click to expand...
I also receive my PGM mobo today from Sheep Nova. And yes, my tracking number also ended in GB. My parcel was in Heathrow too.

Unfortunately I can't use this mobo. I'm using a Supergun and I have sound but the image is trembling. In other TV that I have the AV simbol is on the screen all the time and there's no sound.
Both TV's are CRT.


Damm it! My Ketsui cartridge arrives tomorrow (DDP next week) an I can't play it ;(
 
I'm using real arcade RGB monitor (MS9, and PFX, also a Philips CMsomething 'New Media System 17xx') and have no issues on any of them.
Trembling image usually means your tv/monitor can't handle the resolution/signal.. :(
 
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