Interface - Hitachi 902 Service Manual

15.4.3 Interface

(1) System
(2) Transmission speed
(3) Sync system
(4) Handshaking
(5) Input/output level
(6) Input/output conditions
• DATA 1 to 8, FEED, INIT
• STB
• BUSY, ACK, PE, ERROR
NOTE: Both Fanin and Fanout are set to "1", 74LS or equivalent is connected on the
host side and a pull-up resistor (4.7 k Ω) is provided in the final stage.
: Conforming with Centronics standards (8-bit parallel)
: 1000 cps
2000 bps (bytes/second)
: Externally fed strobe pulse
: ACK/BUSY signal
: TTL level
Vcc
4.7 kΩ
Vcc
4.7 kΩ
1000 PF
Vcc
4.7 kΩ
Character mode
Graphic mode
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