| ??? 06/29/07 00:45 Modified: 06/29/07 00:52 Read: times |
#141322 - PSTN Modem on 3 wire RS232 |
I am curently using a 9 wire RS232 interface from a 8052 micro to a PSTN modem. This device dials out and also recieves connections.
a new version of this device now only supports a 3 wire rs232 interface to the pstn modem (It was decided it was easyier for software to code around this than hardware to redesign the board). In the code for the 9 wire interface version i have relyed on the carrier detect to detect an incomming connection or loss of an active connection. Now that i no longer have a carrier detect this becomes a bit of a problem. Currently i am looking at the data from the modem on the first UART data interrupt to detect a connection (Unless any one has a better idea??) im not sure how i am going to detect a loss of connection?? has any one done something simalar and can help me out with a few ideas? |
| Topic | Author | Date |
| PSTN Modem on 3 wire RS232 | 01/01/70 00:00 | |
| Easier for software?? | 01/01/70 00:00 | |
| Unfortunate | 01/01/70 00:00 | |
| Flow control | 01/01/70 00:00 | |
| The end of the food chain | 01/01/70 00:00 | |
| AT Unsolicited Responses | 01/01/70 00:00 | |
| isn't possible to use some AT-commands? | 01/01/70 00:00 | |
| Yes! | 01/01/70 00:00 | |
| in-band/out-of-band | 01/01/70 00:00 | |
| Thank you | 01/01/70 00:00 | |
Ignore flow control? | 01/01/70 00:00 |