2-2. Interface Circuit
2-2-1. RS-232C Serial Interface
Input (RXD, CTS)
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75189 or equivalent
Output (DTR, FAULT, TXD, RCH, RTS)
Printer |
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75188 or equivalent
Fig .
Input (TTY-RXD, TTY-RXDR)
Host computer
+V
Printer |
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Output (TTY-TXD, TTY-TXDR)
Host computer
+V
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| Printer | R | |
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Note: Adjust “R” so that the loop current is set within 10 to 20 mA.
Fig. 2-2 Current loop interface circuit
– 8 –