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Lines 1454-1469
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| 1454 |
rhcnt = 0; |
1454 |
rhcnt = 0; |
| 1455 |
traceFCF(dir == FCF_SNDR ? "SEND send" : "RECV send", FCF_CRP); |
1455 |
traceFCF(dir == FCF_SNDR ? "SEND send" : "RECV send", FCF_CRP); |
| 1456 |
} |
1456 |
} |
| 1457 |
startTimeout(ms); |
1457 |
do { |
| 1458 |
if (!(atCmd(rhCmd, AT_NOTHING, 0) && waitFor(AT_CONNECT,0))) { |
1458 |
lastResponse = AT_NOTHING; |
| 1459 |
stopTimeout("waiting for v.21 carrier"); |
1459 |
startTimeout(ms); |
| 1460 |
if (wasTimeout()) { |
1460 |
if (!(atCmd(rhCmd, AT_NOTHING, 0) && waitFor(AT_CONNECT,0))) { |
| 1461 |
abortReceive(); |
1461 |
stopTimeout("waiting for v.21 carrier"); |
| 1462 |
setTimeout(false); |
1462 |
if (wasTimeout()) { |
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|
1463 |
abortReceive(); |
| 1464 |
setTimeout(false); |
| 1465 |
} |
| 1466 |
if (lastResponse != AT_NOCARRIER || rhcnt++ > 30) return (false); |
| 1463 |
} |
1467 |
} |
| 1464 |
return (false); |
1468 |
stopTimeout("waiting for v.21 carrier"); |
| 1465 |
} |
1469 |
/* |
| 1466 |
stopTimeout("waiting for v.21 carrier"); |
1470 |
* The meaning of a direct NO CARRIER response/result to the AT+FRH=3 |
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|
1471 |
* command can be interpreted two ways due to wording in ITU T.31. |
| 1472 |
* The more traditional interpretation is that it is out-of-spec: that |
| 1473 |
* a NO CARRIER response should only come after a CONNECT message. |
| 1474 |
* However, T.31 gives sample sessions that illustrate precisely this |
| 1475 |
* kind of out-of-spec sequence: |
| 1476 |
* |
| 1477 |
* <-- AT+FRH=3 |
| 1478 |
* --> NO CARRIER |
| 1479 |
* |
| 1480 |
* And the interpretation is clear to indicate that in this case the |
| 1481 |
* modem detected a carrier, but it apparently was not V.21 HDLC, and |
| 1482 |
* the NO CARRIER response indicates that the indeterminate carrier |
| 1483 |
* has dropped. This functionality is more cumbersome than it is |
| 1484 |
* helpful (its value is not much different than that of an AT+FRS=1 |
| 1485 |
* command), and what it really means is that we just need to re-issue |
| 1486 |
* the AT+FRH=3 command until we get something useful as this scenario |
| 1487 |
* will most likely occur on incidence of Phase C premature carrier loss. |
| 1488 |
*/ |
| 1489 |
} while (lastResponse == AT_NOCARRIER); |
| 1467 |
} |
1490 |
} |
| 1468 |
frame.reset(); |
1491 |
frame.reset(); |
| 1469 |
gotframe = recvRawFrame(frame); |
1492 |
gotframe = recvRawFrame(frame); |
