Error handling
A* character is printed if a parity error, framing error, or overrun error is detected.
Pin assignments
The serial interface connector pin assignments and a description of the interface signals are shown in the table below. The direction of signals is given as viewed from the printer.
Signal pin | Direction | Description |
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2 | TXD | OUT | Transmits data. This pin |
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| transmits serial data from the |
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| printer to the computer. |
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3 | RXD | IN | Recived data. This pin |
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| transmits data from the |
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| computer to the printer. |
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4 | RTS |
| Always + 12V |
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5 | CTS | IN | Always ignored |
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| A | ||||
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6 | DSR | IN | Data set ready. |
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7 |
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| Signal ground |
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20 | DTR | OUT | Data terminal ready. This pin |
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| indicates whether or not the |
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| printer is ready to receive |
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| data. If the printer ready |
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| protocoil is not selected, the |
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| printer is always ready to |
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| receive data (this pin is always |
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| HIGH.) If the printer ready |
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| protocoil is selected, the |
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| printer can accept data |
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| when the pin level is LOW. |
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| When the DTR signal goes |
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| LOW, the host computer must |
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| stop sending data within 256 |
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| characters. This function can |
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| be set on or off with the |
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| printer. |
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