Okay  Yes, the Konami-1 cpu runs @ 2 Mhz. However the chip package has extra pins, so I cannot replace it with a regular 6809. Also, as far as I know based on mame source code, the konami-1 cpu is a regular 6809 with some scrambled lines. However, I don't know yet if only the opcodes are scrambled or data also. If both data and opcodes are scrambled, it should be pretty straightforward to descramble it.
Also, the sprite hardware uses 4 sram with unknown yet reference, so I cannot test them.
The worst is all worked perfectly a single time yesterday.
Then after powering-off and powering-on again, I got the same problem: sprites missing.
Maybe it is related to bad synchronization between the two cpu (z80 and 6809), or bad reset. But the reset seems to work ok as far as I have tested.
Next step will be to test the 2x27C245 and 2x27C244 used on the konami-1 bus and also the 2128 ram which is soldered.
Any information / help appreciated 
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Re: Gyruss diagnostic roms
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Yes, the Konami-1 cpu runs @ 2 Mhz. However the chip package has extra pins, so I cannot replace it with a regular 6809. Also, as far as I know based on mame source code, the konami-1 cpu is a regular 6809 with some scrambled lines. However, I don't know yet if only the opcodes are scrambled or data also. If both data and opcodes are scrambled, it should be pretty straightforward to descramble it.
