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difference between TSROM and TLROM
by coinheaven on 2007-03-20 (#22530)
is it possible to tell the difference if a rom uses a TSROM or a TLROM using an emulator? i use the image info function on the Nestopia emulator. if this isnt possible, how do you tell?
If it has the battery bit set, it's TKROM. If it executes in PRG RAM ($6000-$7FFF), it's TSROM (same as TKROM without the battery circuit). If it writes to PRG RAM and expects to read the same thing back, it's TSROM. Otherwise, it's TLROM.
Actually there is no current way to know, but when iNES 2.0 will be effective in therory this will be fixed.
Only a few games actually relies to have SRAM at $6000-$7fff absent (Low G Man comes to mind, and if run with a TSROM configuration (with SRAM) I've heard it will freezes (not tested myself). Recent emulators probably check this one with CRCs).
How about adding a 6264 to make a TLROM have the extra ram to function like a TSROM? I've seen threads about piggy backing on top of the PRG but I'm unsure exactly how to do it. If anyone has diagrams that would be awesome.