1.2 Video Controller Circuit
(1) CPU block
CPU
RISC chip
Clock speed: 19.6608 MHz
Appearance:
(2)ASIC/Gate Array Block
•HG51CS265FD (Hitachi) -
Controls the address decoder, timers, interfaces (Centronics and
•µPD65632GC (NEC) -
(3)Font Cartridge/Card Block
•Font cartridge (option)
The font cartridge has a 64MB memory area and is controlled by the
•Font Card (option)
The font card has a 64MB memory area and is controlled by the
The card is supplied with 12V power because the flash card requires 12V power supply when writing or erasing data.
The address bus is buffered by LS244 and the data bus, is buffered by LS245.
(4)
•Centronics parallel interface
Data transmission and reception are controlled by the HG51CS265FD .
•
Data transmission and reception are controlled by the HG51CS265FD . The ADM202JRN serves as driver/receiver.
(5)SIMM block
•SIMM
•2 SIMM sockets are available.
•SIMM should be of
•6 types of SIMM (1MB, 2MB, 4MB, 8MB,16MB and 32MB) can be combined: 1MB
2MB
32MB
1)The SIMMs have its printed marking on the PCB by silk screen: SLOT1, and SLOT2, respectively. The SIMMs should be set in the order of SLOT1 - SLOT2.
2)SIMMs should be set in the order of its memory size and in the order of SLOT No. Example: 2 SIMMs: 1MB, and 4MB