Epson Multi-mode Data Controller MFJ-1278B User Manual
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MFJ-1278B MULTI-MODE HARDWARE
TTL INTERFACE PORT PIN FUNCTION,J5
The MFJ-1278B provides the user with a TTL level I/O port, J5. The TTL level I/O port, J5
is compatible with computers and terminals that do not support RS-232C serial voltage
levels, such as the Commodore C64 and C128 computers. Voltage levels of 0 and 5 VDC are
available at J5. Below in Table 8-3 is the pin out of the TTL level I/O port, J5:
Table 8-3 TTL Port, J5 Pin Out
J5 Pin #
Pin Function
1
Receive Data
2
Data Carrier Detect
3
Ground
4
Request to Send
5
Transmit Data
6
Data Set Ready
7
Clear to Send
8
Frequency Shift Keying
9
Space Output for Scope
10
Mark Output for Scope