TINY-2/MICRO-2 Technical Ref., 2. Ed 1989
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"Eight-wire" RS-232 Cable
Computer DB-25
or
DE-9 to TINY-2/MICRO-2 DE-9P
1 –––––––– Shell –––––––– 5
2 ––––––––– 3 –––––––––– 3
3 ––––––––– 2 –––––––––– 2
4 ––––––––– 7 –––––––––– 7
5 ––––––––– 8 –––––––––– 8
6 ––––––––– 6 –––––––––– 6
7 ––––––––– 5 –––––––––– 5
8 ––––––––– 1 –––––––––– 1
"connected" signal
20 –––––––– 4 –––––––––– NC
Non-Standard RS-232C Serial Ports
NOTE: Some computers which require an external TTL to RS-232 adapter to support an RS-232 se-
rial port may be interfaced to the TINY-2/MICRO-2 without the RS-232 adapter unit by using the
TINY- 2/MICRO-2 TTL level signals.
Computers with non-standard RS-232 serial ports must meet the following conditions:
Voltage levels sent by the computer must be greater than +3 Volts in one state and less than
-3 Volts in the other state.
The polarity of the signals must conform to the RS-232C standard, i.e. the low voltage state is
a logical "1" and the high voltage state is a logical "0".
Make or buy a cable that provides the following connections:
The computer serial port common (ground) pin must be tied to the TINY-2/MICRO-2 serial port
connector pin 5.
The signal line that sends data from the computer must be tied to the TINY-2/MICRO-2 con-
nector pin 3.
The pin on which the computer receives data must be tied to the TINY-2/MICRO-2 connector
pin 2.
The documentation provided with the computer or its accessory serial port should clarify any re-
quirements for additional signals.
