Ok, now I have 2 assembled boards available. Does anyone want to buy them? I would like to ask 10 euros for the fully assembled board + shipment (4 euro within EU).
Hi...i am a new user here. As per my knowledge the 128K on the daughter board, only CAS0 is routed to the daughter board connector on YIS503/II. Also only 64Kbytes of VRAM can be addressed per CASx bank. Therefore maximum 64 KBytes of VRAM can be addressed by the plug-in board which makes it compatible with the MSX2.When working with 128K of VRAM, putting one big DRAM chip with an additional logic wouldn't help, since V9938 uses the bank interleaved access in screen 7 & 8.
Hi...i am a new user here. As per my knowledge the 128K on the daughter board, only CAS0 is routed to the daughter board connector on YIS503/II. Also only 64Kbytes of VRAM can be addressed per CASx bank. Therefore maximum 64 KBytes of VRAM can be addressed by the plug-in board which makes it compatible with the MSX2.When working with 128K of VRAM, putting one big DRAM chip with an additional logic wouldn't help, since V9938 uses the bank interleaved access in screen 7 & 8.
The board is designed to get CAS0 from the connector and CAS1 via the additional wire connected to the VDP's pin.
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