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Mapper 34 (BxROM) and Mapper 11 (Colordreams) the same?

Mapper 34 (BxROM) and Mapper 11 (Colordreams) the same?
by on (#103355)
Are Mapper 34 and Mapper 11 identical when there is no CHR ROM, and 128k of PRG ROM? I noticed that you can change the NES header between games that meet those conditions. Wally Bear works as mapper 34, and Deadly Towers works as mapper 11.

Did Wally Bear get the correct mapper number assigned to it?
Re: Mapper 34 (BxROM) and Mapper 11 (Colordreams) the same?
by on (#103363)
A game can run under any mapper number that correctly describes its behavior. For example, any NROM-128, -256, or -368 (#0) game can run as CNROM (#3), and any CNROM game with PRG ROM <= 32K and CHR ROM <= 128K can run as GNROM.

If PRG size <= 128K, CHR size <= 8K, and the console is toploading, then mapper 11 and mapper 34 are equivalent. But mapper 11 also contains CIC stun control bits, and I don't know whether that particular board runs any traces to the CHR RAM. It does use a 74LS377 like mapper 11 boards do, but so would the oversize #34 board that I had originally planned for Action 53 until infiniteneslives asked me to come up with a new design to incorporate UNROM, CNROM, and AOROM support.
Re: Mapper 34 (BxROM) and Mapper 11 (Colordreams) the same?
by on (#103416)
It looks like NINA-07 can be jumpered either for a 6264 (or a 62256...) or 64kiB CHR-ROM: the two solder pads in the top center control whether A14 or CHRnWR are connected to the pin 27. Regardless, pins 26 and 1 (A13-or-CE2 and A15-or-n/c) are always routed to CHR.