MEMORY PLUS Manual By Lee Davison and Hans Otten Back to The Computerist
The following connections must be made between the MICRO and the MEMORY PLUS board before any EPROM Programming can take place: MICRO A-9 to MP A-19 Port B Bit 0 (PB0) Address Bit 8 for EPROM MICRO A-10 to MP A-20 Port B Bit 1 (PB1) Address Bit 9 for EPROM MICRO A-11 to MP A-21 Port B Bit 2 (PB2) Address Bit 10 for EPROM If the MEMORY PLUS board is mounted in its normal position, directly below the MICRO, it may be difficult or impossible to get access to the EPROM socket for programming. There are two ways around this problem. 1. Use a 24 pin header to bring wires directly from the EPROM Programming Socket out to a more accessible location. 2. Attach wires for an additional EPROM Programming Socket directly to the MP application connector. All of the lines necessary for attaching an external EPROM Programming Socket are available: EPROM Socket MP Application Function Connector 1 A-15 Address bit7 from VIA PB7 2 A-B Address bit6 from VIA PB6 3 A-16 Address bitS from VIA PBS 4 A-13 Address bit4 from VIA PB4 5 A-12 Address bit3 from VIA PB3 6 A-11 Address bit2 from VIA PB2 7 A-10 Address bit1 from VIA PB1 8 A-9 Address bit0 from VIA PBO 9 A-14 Data bit 0 from VIA PA0 10 A-2 Data bit 1 from VIA PA1 11 A-3 Data bit 2 from VIA PA2 12 A-1 Ground 13 A-4 Data bit 3 from VIA PA3 14 A-5 Data bit 4 from VIA PA4 15 A-6 Data bit S from VIA PAS 16 A-7 Data bit 6 from VIA PA6 17 A-8 Data bit 7 from VIA PA7 18 A-18 Program Pulse Inverted from VIA CB2 19 (MICRO A-11) A-21 Address bit 10 from MICRO PB2 20 A-F Chip Select from VIA CA2 21 A-22 +25V direct or from +27 to +30 regulator 22 (MICRO A-10) A-20 Address bit 9 from MICRO PB1 23 (MICRO A-9) A-19 Address bit 8 from MICRO PB0 24 (MICRO A-A) A-A +5V regulated The addressing for the EPROM Socket only consists of eleven (11) bits. This means that addressing for programming purposes runs from 0000 to 07FF, regardless of the actual address that the EPROM will eventually reside at. The high order five (5) bits of EPROM address are totally defined by which socket the EPROM is placed in and where the set of EPROMs are switched to: 2000, 4000,..., E000.