HMI-640S is shipped together with a serial cable (NULL modem cable) for customers to make a direct connection between it and the host PC. Note that off-the-shelf NULL modem cables may not be wired correct- ly. The following list is the wiring table for this cable:
9-pin NULL Modem Cable:
| Remoet host | Calling system | |
| serial port | serial port | Signal |
| connector | connector | |
| | | |
| 3 | 2 | Transmit Data |
| | | |
| 2 | 3 | Receive Data |
| | | |
| 7 | 8 | Request to Send |
| | | |
| 8 | 7 | Clear to Send |
| | | |
| 6,1 | 4 | Data Set Ready |
| and Carrier Detect |
| | |
| | | |
| 5 | 5 | Signal Ground |
| | | |
| 4 | 6,1 | Data Terminal |
| Ready |
| | |
| | | |
8 0 HMI-640S User's Manual
