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SLROM with battery-backed CHR-RAM?

SLROM with battery-backed CHR-RAM?
by on (#211658)
While perusing the leaked original Nintendo MMC1 datasheet (March 26, 1987 revision), I noticed that the "cassette repertoire" on page two included two entries with 128/256 KiB PRG-ROM, 8 KiB CHR-RAM, and a battery that is described as backing the CHR-RAM, and this board is called "SLROM". Apparently, Nintendo originally had different ideas for SLROM...
Re: SLROM with battery-backed CHR-RAM?
by on (#211672)
Without access to said leaked datasheet, there's not much we can comment. However, I must say the board you describe sounds like SKROM, and even games that ended up being mass produced on SLROM boards were usually prototyped with SKROM boards with the RAM absent from the board.
Re: SLROM with battery-backed CHR-RAM?
by on (#211675)
You must have had access to it at some point, as you posted a response in the thread in which a link to them was provided. I could repost the datasheet, although there seemed to have been some trepidation expressed in that thread against doing so.
Re: SLROM with battery-backed CHR-RAM?
by on (#211700)
On the page, at the bottom, it explicitly says something that google translates as "Battery backup RAM of character area".

It also calls it out as the "SM" type of "SLROM"
Re: SLROM with battery-backed CHR-RAM?
by on (#211705)
I suppose that since it has already been posted in another thread, it's okay to post the page, otherwise tell me and I'll remove it.
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