If I recall properly, the hassle is in missing RTC.
Anyone knows why problem happens, and what to modify in ROM to make it running without RP5C01. Thanks.
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Well, I have removed some code in the ext rom which checks for RTC, and in bluemsx combination works (Enable CMOS and Use charged battery are both unchecked). However the same ROM combination, installed into the real MSX does not work - no picture at all. Are there any other MSX2 ports missing where it can hang?
Machine does not get to VRAM initialization - its R/W line is always high. It does not get to VDP at all - /CSW (30) and /CSR (31) are always high. (and of course CAPS led does not work...)
Solved. There was resistor R315 missing (4.7K, pull-up for EXT ROM's PGM pin 27), which is not documented in any version of the family of these machines.
That was not the last problem. System did not work properly and I found ou that Guillermo was right - some chips related to memory mapper were missing on the board.
Now my problem looks like:
In screen 2 and 3 everything is fine.
In higher screen modes sprites (only sprites!) are corrupt and flashing. I tried with King's Valley 2 and Usas. Why could it be? Important to mention that I replaced DRAMs with 2 SRAMs of 64K each (with some addon logic to keep proper signalling of SRAMs according to /RAS and /CAS signals).