32Mbit Multirom 2in1 diagram
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1. NO BLATANT PIRACY. This includes reproducing homebrew less than 10 years old, with the exception of free software.
2. No advertising your reproductions, with the exception of free software.
3. Be nice. See RFC 1855 if you aren't sure what this means.
32Mbit Multirom 2in1 diagram
Hello,
Can somebody share schematic diagram for 32Mbit Multirom EPROM 2in1 ?
I tried to use 74HC74 flip-flop chip for 2 games x 16Mbit with this diagram but it doesn't work.
I use method of combine two files with command line "copy /b"
Thank for help.
Can somebody share schematic diagram for 32Mbit Multirom EPROM 2in1 ?
I tried to use 74HC74 flip-flop chip for 2 games x 16Mbit with this diagram but it doesn't work.
I use method of combine two files with command line "copy /b"
Thank for help.
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- Joined: Fri Jun 24, 2016 4:20 pm
Re: 32Mbit Multirom 2in1 diagram
poorstudenthobbyist wrote: ↑Tue Feb 02, 2021 3:00 pm https://thepoorstudenthobbyist.com/2020 ... -overview/
Thank you!
Re: 32Mbit Multirom 2in1 diagram
So, if i get right...poorstudenthobbyist wrote: ↑Tue Feb 02, 2021 3:00 pm https://thepoorstudenthobbyist.com/2020 ... -overview/
- For 2X16mbit on one 322 eprom: use adress pin A21
- For 4X8mbit on one 322 eprom: use adress pin A21 and A20
Is that right?
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Re: 32Mbit Multirom 2in1 diagram
Technically A20 and A19, since it's a 16-bit databus, but yep the highest address pins.
Re: 32Mbit Multirom 2in1 diagram
Why technically ?poorstudenthobbyist wrote: ↑Wed Feb 03, 2021 8:49 am Technically A20 and A19, since it's a 16-bit databus, but yep the highest address pins.
Re: 32Mbit Multirom 2in1 diagram
The datasheet for the 27C322 calls those pins A19 and A20.
But in a machine using a 68000, those same pins are connected to 68k A20 and A21.
But in a machine using a 68000, those same pins are connected to 68k A20 and A21.
Re: 32Mbit Multirom 2in1 diagram
I tried to do for 4in1 (4x8Mbit) like that, but it's doesn't work ...
Why? Is there something wrong?
For LoROM :
A21=> pin 42 (27C322)
A20=> pin 1 (27C322)
Re: 32Mbit Multirom 2in1 diagram
Uh. You might to look more closely at what you wrote.
Re: 32Mbit Multirom 2in1 diagram
Thats why it not working
Here is corrected visual schematic for 27C322 LoROM / HiROM with 74HC74 flip-flop chip:
How about SAVES ?
Will it works to save game progress ?
If for example, I have one file with 2 games that each of ONE need SRAM 6264 (8kB), can I keep ONE SRAM 6264 for two games?
Or better to put bigger SRAM, like 62256 ?
Re: 32Mbit Multirom 2in1 diagram
I I will use 2in1 multirom,
How to do if both 2 games will using 64K SRAM CHIP ?
Will it work with one ?
How to do if both 2 games will using 64K SRAM CHIP ?
Will it work with one ?
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Re: 32Mbit Multirom 2in1 diagram
Apply the same method in the multicart article to the SRAM. It holds data in the same way as a ROM does (it just gets erased if power is removed).
Re: 32Mbit Multirom 2in1 diagram
Ok,poorstudenthobbyist wrote: ↑Tue Feb 09, 2021 5:49 pm Apply the same method in the multicart article to the SRAM. It holds data in the same way as a ROM does (it just gets erased if power is removed).
but Will it be good enough one SRAM 64 for two games that each one need 64 ?
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Re: 32Mbit Multirom 2in1 diagram
Can you put two 32Mbit ROMs on one 27C322?
Re: 32Mbit Multirom 2in1 diagram
No.
I talking about 2 games x 16Mbit = 32 Mbit (27C322 Multirom)
But each 16Mbit game need 6264 SRAM.
If on my board I will keep one 6264 SRAM, I dont know how each game will save data, will it be good enough space for each one?