Thanks, it says the Z80 runs at 4.1MHz which makes the strange /7 frequency divider plausible. 30KB RAM total (15 SRAM chips of 2KB each)
Is this video yours? You can indeed see the 15 SRAM chips, the chip next to the Z80 is probably the BIOS ROM. The 3 QFP are mentioned in the manual as "ATC"(?), I/O, and VRAM controller.
Robbbert it looks like you got Sekigahara working correct? Did you get a chance to mess with the 8K dumps of Motocross yet to see if they work as well? No rush just mainly asking as in order to get gameplay video/pics to help with the emulation I'll need to reseat and resolder the chips and would like to make sure those dumps look good before I do that.
if you invert the polarity on the tape files, it detects the header, and loads a bunch of data into RAM, but seems to stop loading when it reaches another area, before the end of the tape. lots of strings in RAM, so it's definitely loading *something* valid off the tape, but not sure how much of it is valid, or why it needs the polarity inverting.
ah, you have to invert the polarity, then run it with the BASIC cart inserted, I was trying to get it to verify, before even trying it with the BASIC.
it still seems to stop loading before the end, but maybe it's meant to..
also if I do 'V' (verify) instead of 'L' it says checksum error immediately after trying to load the header still (which is weird because at that point it really doesn't have much to checksum)
it's some kind of graphing program, written in basic, I have no idea if it works properly.
Interesting. Verify would most likely be comparing the tape against the existing program in RAM (which isn't there), rather than just checking the checksums.
Since this is the first real tape we've ever had for this system, it's quite possible that the signal needs inverting in emulation. I'll assume that is so, and make the change.
in that case verify gives a checksum error near the point where it stops loading but the data continues.
if I do a list, there's clearly a complete basic program in there, so I guess the part being loaded at the time are variables stored with the basic program, which means maybe it isn't loading the very last part? but I'm not sure there's room in RAM to load anything more anyway.
but yeah if there are no other tapes to compare against, assume it needs inverting in the emulation .