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Re: Contra - Revenge of the Red Falcon

Posted: Tue Sep 27, 2016 4:08 am
by Fisher
Pin 2 seems tied to GND.
It should not, since it's A16.
I've put the ROM pin numbers on this schematic:
UxROM_circuit.jpg
I hope this helps.

Re: Contra - Revenge of the Red Falcon

Posted: Tue Sep 27, 2016 8:20 am
by lidnariq
I can't quite tell in that picture, but is pin 30 connected to both ROM pin 32 and 74'32 pin 8? That's not right....

Re: Contra - Revenge of the Red Falcon

Posted: Tue Sep 27, 2016 10:16 am
by Tormenter
lidnariq wrote:I can't quite tell in that picture, but is pin 30 connected to both ROM pin 32 and 74'32 pin 8? That's not right....

In the pic no, (30 lifted, tied to pin 8 of 74'32). I also tried leaving pin 30 in the hole and tying it to pins 31/32

Re: Contra - Revenge of the Red Falcon

Posted: Tue Sep 27, 2016 10:18 am
by Tormenter
Fisher wrote:Pin 2 seems tied to GND.
It should not, since it's A16.
I've put the ROM pin numbers on this schematic:
UxROM_circuit.jpg
I hope this helps.

Not really sure how to read those things lol. But pin 2 is tied to hole 22 of the pcb (under lifted pin 24 of the chip)

Re: Contra - Revenge of the Red Falcon

Posted: Tue Sep 27, 2016 10:33 am
by lidnariq
You stole the wrong OR gate in the 74'32. The one on pins 8-10 was already being used.

Look at the reverse side of the PCB.

Re: Contra - Revenge of the Red Falcon

Posted: Tue Sep 27, 2016 11:34 am
by Tormenter
lidnariq wrote:You stole the wrong OR gate in the 74'32. The one on pins 8-10 was already being used.

Look at the reverse side of the PCB.

Not sure what you are saying =( hehe

Re: Contra - Revenge of the Red Falcon

Posted: Wed Sep 28, 2016 5:19 am
by Fisher
Well, take a look at the picture I posted.
If you rotate it to the right, you'll have the exact position of the 74LS32 and the 74LS161.
The pins are also drawn on the same IC pins position.
I tried to do a quick (and dirty) example, hope this helps:
2hwpjie.jpg

Re: Contra - Revenge of the Red Falcon

Posted: Wed Sep 28, 2016 5:45 am
by Ice Man
Really? Pin 30 is lifted up and ONLY connected to pin 8 of the 74'32.

I cannot make it more clear.

PRG ROM:
Bend up pin 1, 2, 24, 30, 31 and 32 of 27C040 EPROM
Pin 1 is not connected anywhere
Solder pin 2 to hole 22 (A16)
Solder pin 24 to GND (OE)
Solder pin 30 to 74'32 pin 8
Solder pin 31 to hole 28 (+5V)
Solder pin 32 to hole 28 (+5V)

UNROM -> UOROM:
Bend up pin 6 of 74'161
Bend up pin 9 and pin 10 from 74'32
Connect pin 9 from 74'32 to pin 2 74'32
Connect pin 11 of 74'161 to pin 10 of 74'32
Connect pin 6 of 74'161 to D3 of PRG ROM (DO NOT LIFT THIS PIN OF PRG ROM!)
Connect pin 8 of 74HC32 to pin 30 (A17) of PRG ROM (LIFT THIS PIN!)

There's really nothing else I can add/do. Schematics already showed how it's soldered.

Otherwise get an UOROM donor or check the connections with a multi meter.

Re: Contra - Revenge of the Red Falcon

Posted: Wed Sep 28, 2016 8:13 am
by lidnariq
The NES-UNROM-09 PCB uses the three OR gates on 74'32 pins 1-3, 8-10, and 11-13. Rewiring instructions that say to use the OR gate on pins 8-10 won't work on this donor! You'll have to use pins 4-6 for the added address line, and unfortunately Tormenter will now have to repair pins 8-10.

Look at back side of the PCB.

Re: Contra - Revenge of the Red Falcon

Posted: Wed Sep 28, 2016 9:02 am
by Tormenter
Ice Man wrote:Really? Pin 30 is lifted up and ONLY connected to pin 8 of the 74'32.

I cannot make it more clear.

PRG ROM:
Bend up pin 1, 2, 24, 30, 31 and 32 of 27C040 EPROM
Pin 1 is not connected anywhere
Solder pin 2 to hole 22 (A16)
Solder pin 24 to GND (OE)
Solder pin 30 to 74'32 pin 8
Solder pin 31 to hole 28 (+5V)
Solder pin 32 to hole 28 (+5V)

UNROM -> UOROM:
Bend up pin 6 of 74'161
Bend up pin 9 and pin 10 from 74'32
Connect pin 9 from 74'32 to pin 2 74'32
Connect pin 11 of 74'161 to pin 10 of 74'32
Connect pin 6 of 74'161 to D3 of PRG ROM (DO NOT LIFT THIS PIN OF PRG ROM!)
Connect pin 8 of 74HC32 to pin 30 (A17) of PRG ROM (LIFT THIS PIN!)

There's really nothing else I can add/do. Schematics already showed how it's soldered.

Otherwise get an UOROM donor or check the connections with a multi meter.

It is a 256k rom, so using a 27C020 if that matters?

Re: Contra - Revenge of the Red Falcon

Posted: Wed Sep 28, 2016 9:06 am
by Tormenter
lidnariq wrote:The NES-UNROM-09 PCB uses the three OR gates on 74'32 pins 1-3, 8-10, and 11-13. Rewiring instructions that say to use the OR gate on pins 8-10 won't work on this donor! You'll have to use pins 4-6 for the added address line, and unfortunately Tormenter will now have to repair pins 8-10.

Look at back side of the PCB.

So which revision of the UNROM # should Use with the wiring info Ice Man provided?

Re: Contra - Revenge of the Red Falcon

Posted: Wed Sep 28, 2016 10:20 am
by Ice Man
Doesn't matter if it's a 27C020. However, what EPROM is it? Brand, etc..
I've had EPROMs where PGM had to be grounded.

Either way, I never knew that certain revisions had another pinout. So far all UOROM games I did (using Famicom games only so far) worked fine with that method.

Re: Contra - Revenge of the Red Falcon

Posted: Wed Sep 28, 2016 12:18 pm
by lidnariq
Tormenter wrote:So which revision of the UNROM # should Use with the wiring info Ice Man provided?
Looks like ... none of them?

AFAICT, every single revision of both US and European NES-UNROM leaves the unused OR gate on pins 4-6 instead. NesCartDB doesn't have any backs for PCB revisions before NES-UNROM-04, but even the top shows traces connected to pins 8-10 and not to pins 4-6.

So the "use pins 8-10" instructions must be for Famicom HVC-UNROM boards only...

Re: Contra - Revenge of the Red Falcon

Posted: Wed Sep 28, 2016 3:19 pm
by Tormenter
krzysiobal wrote:Works fine.
Image Image
Do you happen to have any pics of the board you are using?

Re: Contra - Revenge of the Red Falcon

Posted: Thu Sep 29, 2016 1:21 pm
by Tormenter
Would you wire it to a UOROM (Say Paperboy 2) the same as you would wire a regular UNROM board? I noticed the UOROM has the 4 extra pin holes (Pins 1, 2, 31, 32)