SNES M27C801 2in1 HiRom games - Diagram for Flip-flop 74HC74

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Kayumba
Posts: 87
Joined: Sun Mar 01, 2020 2:36 am

Re: SNES M27C801 2in1 HiRom games - Diagram for Flip-flop 74HC74

Post by Kayumba » Thu May 28, 2020 2:39 pm

lidnariq wrote:
Thu May 28, 2020 2:21 pm
Have you already made a reproduction without using the 74'74?
yes
lidnariq wrote:
Thu May 28, 2020 2:21 pm
If so, what did you do there?
For Hirom
My pin30 of 27C801 (originally A17) connected to pad 44 of PCB (which is A19)

For LoROM
My pin30 of 27C801 (originally A17) connected to pad 45 of PCB (which is A19)

After SWAP BIN method, pin30 of 27C801 digitally became A19.

So when you said :
"the 74'74 should be connected to A19"
My question is to confirm that you are talking about A19 of 27C801 (pin1) or after SWAP BIN method A19 = pin30 ?

lidnariq
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Location: Seattle

Re: SNES M27C801 2in1 HiRom games - Diagram for Flip-flop 74HC74

Post by lidnariq » Thu May 28, 2020 2:44 pm

The pin that is functionally used as A19, to distinguish between the first half and the second half of the data you programmed.


(that is, pin 30)

Kayumba
Posts: 87
Joined: Sun Mar 01, 2020 2:36 am

Re: SNES M27C801 2in1 HiRom games - Diagram for Flip-flop 74HC74

Post by Kayumba » Thu May 28, 2020 2:48 pm

lidnariq wrote:
Thu May 28, 2020 2:44 pm
The pin that is functionally used as A19, to distinguish between the first half and the second half of the data you programmed.


(that is, pin 30)
If so, you talking about pin30 of 27C801 (originally A17 => became A19 after swap method).
I will try to do some test this week-end.

Kayumba
Posts: 87
Joined: Sun Mar 01, 2020 2:36 am

Re: SNES M27C801 2in1 HiRom games - Diagram for Flip-flop 74HC74

Post by Kayumba » Fri May 29, 2020 2:35 pm

Thank you

Kayumba
Posts: 87
Joined: Sun Mar 01, 2020 2:36 am

Re: SNES M27C801 2in1 HiRom games - Diagram for Flip-flop 74HC74

Post by Kayumba » Sat May 30, 2020 4:22 pm

Yes It's WORK!
Thank's.
Here is final diagram of LoROM/HiROM 2in1 games - for Flip-flop 74HC74 and M27C801
Image
This diagram if for SWAP BIN roms.
If you dont use SWAP BIN method, connect pin9 (Data Output 2) of 74HC74 => to pin1 (A19) of M27C801

Image
Last edited by Kayumba on Thu Aug 27, 2020 10:19 am, edited 2 times in total.

Kayumba
Posts: 87
Joined: Sun Mar 01, 2020 2:36 am

Re: SNES M27C801 2in1 HiRom games - Diagram for Flip-flop 74HC74

Post by Kayumba » Wed Aug 05, 2020 9:08 am

Guys,
One question.
Can I use this diagram on one EPROM 27C322 with 4 games of 8mbit (4x8) stitched to one 32MBIT file?

Kayumba
Posts: 87
Joined: Sun Mar 01, 2020 2:36 am

Re: SNES M27C801 2in1 HiRom games - Diagram for Flip-flop 74HC74

Post by Kayumba » Thu Sep 17, 2020 9:47 am

I tried to use the same diagram with not swapped bins (.SMC EPROM).
I just tied pin1 (A19) of M27C801 to Data Out 2
But it doesn't work.

It's work only with swap bins EPROMS.
Whats wrong?
If it's always A19, why its dont work anymore ?
Image
Last edited by Kayumba on Thu Sep 17, 2020 10:23 pm, edited 1 time in total.

Kayumba
Posts: 87
Joined: Sun Mar 01, 2020 2:36 am

Re: SNES M27C801 2in1 HiRom games - Diagram for Flip-flop 74HC74

Post by Kayumba » Thu Sep 17, 2020 5:41 pm

:cry:

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