Parsing NesCartDB XML file: Where's battery-backed VRAM?

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tepples
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Parsing NesCartDB XML file: Where's battery-backed VRAM?

Post by tepples »

I'm trying to develop a program that translates each cartridge in the XML export from BootGod's NesCartDB (mirrored here) into the correct 16-byte NES 2.0 header for this cartridge. I've hit my first snag.

The NesCartDB entry for RacerMate Challenge II shows that both VRAMs are battery-backed. Normally a battery-backed memory will have battery="1". But in this XML document, the battery= attribute appears only in <wram> elements, not <vram> elements. Here's the <cartridge> element in question:

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<cartridge system="NES-NTSC" revision="3.11.088" crc="74920C13"
 sha1="7BFC9DDE8E97F171263EB0C9C84C83705459432C"
 dump="ok" dumper="Skrybe" datedumped="2012-08-30">
  <board type="UNL-RACERMATE" pcb="R981-112-00" mapper="168">
    <prg name="N311088 05/15/91" size="64k" crc="74920C13"
     sha1="7BFC9DDE8E97F171263EB0C9C84C83705459432C"/>
    <vram id="0" size="32k"/>
    <vram id="1" size="32k"/>
    <chip type="74xx00"/>
    <chip type="74xx00"/>
    <chip type="74xx174"/>
    <chip type="74xx174"/>
    <chip type="74xx32"/>
    <chip type="74xx32"/>
    <chip type="74xx4040"/>
    <cic type="337002"/>
    <pad h="0" v="1"/>
  </board>
</cartridge>
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Myask
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Joined: Sat Jul 12, 2014 3:04 pm

Re: Parsing NesCartDB XML file: Where's battery-backed VRAM?

Post by Myask »

Well, for one, that it's showing both as backed conflicts with the bit calling for [ed: forgot words: the CHR-RAM field to be split backed/unbacked] I read in the NES 2.0 spec about Kevtris "tracing out the circuit himself" and "couldn't believe it"… (from when you originally imported his spec to the wiki, for the sake of thoroughness)

ed2: a four-years-older post by kev on same
Last edited by Myask on Thu Sep 07, 2017 3:06 pm, edited 2 times in total.
lidnariq
Posts: 11432
Joined: Sun Apr 13, 2008 11:12 am

Re: Parsing NesCartDB XML file: Where's battery-backed VRAM?

Post by lidnariq »

I've filed an issue against the cart profile.

J1-J4 affect whether both SRAMs, or just U2, are battery backed.
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