7.4 RS232 interface
The RS232 interface is the interface for the application software and the connection to the PC. The customer application communicates with the Modem by AT cellular commands. The RS232 interface is implemented as a
Pin assignments:
Signal | Pin | Input/Output | Description |
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DCD | 1 | Output | Serial port V.24 protocol(for reference) |
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RXD | 2 | Input |
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TXD | 3 | Output |
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DTR | 4 | Output |
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GND | 5 |
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DSR | 6 | X |
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RTS | 7 | Output |
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CTS | 8 | Input |
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RI | 9 | Input |
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15
