Malcolm, Ok, thanks for let us know. I now found video docs for VT340 (dragon system - vipers and adders). Each chip hold one bitmap plane individually. VCB02 graphics card uses the same chips.
I misread schematics. I believe that E80 is NVRAM chip for just settings - 512 x 8, not 512K x 8. Firmware is in ROM cartridge. E49 dump should be labelled as 236E6.bin for CG rom. Does anyone have a copy of CRT 9007 video controller docs for VT220 terminal? Thanks, Tim -----Original Message----- From: malc...@avitech.com.au [mailto:malc...@avitech.com.au] Sent: Saturday, April 15, 2017 9:43 PM To: 'Tim Stark' <fswo...@verizon.net>; 'Cory Smelosky' <b...@gewt.net> Cc: simh@trailing-edge.com Subject: RE: [Simh] DEC VT emulators on MAME I've now pulled apart a spare non-working VT340, for the ROM dumps. This terminal has a faulty power supply and very significant screen burn, so I wasn't planning on repairing it anyway. On my board, E80 is a XICOR X2804AP-45 which is soldered in place. So I haven't removed it or dumped its contents. E49 is a 27256 EPROM. I have dumped the content of that ROM and it is now available here -> http://avitech.com.au/?p=1818 That page also has pictures of the VT340 internals. Tim - I will write to you separately to arrange sending the VT340 logic board to you. Malcolm. _______________________________________________ Simh mailing list Simh@trailing-edge.com http://mailman.trailing-edge.com/mailman/listinfo/simh
