esp_modem CMUX truncates response from AT+CSPI? (IDFGH-15836) #838
Description
Answers checklist.
- I have read the documentation for esp-protocols components and the issue is not addressed there.
- I have updated my esp-protocols branch (master or release) to the latest version and checked that the issue is present there.
- I have searched the issue tracker for a similar issue and not found a similar issue.
What component are you using? If you choose Other, provide details in More Information.
esp_modem
component version
1.4.0
IDF version.
4.4.1
More Information.
We are using the latest esp_modem and are connected using CMUX mode with PPP on a SIMCOM 7672 (76xx family). Our esp_modem configuration is:
#
# esp-modem
#
# CONFIG_ESP_MODEM_CMUX_DEFRAGMENT_PAYLOAD is not set
# CONFIG_ESP_MODEM_USE_INFLATABLE_BUFFER_IF_NEEDED is not set
CONFIG_ESP_MODEM_CMUX_DELAY_AFTER_DLCI_SETUP=0
# CONFIG_ESP_MODEM_CMUX_USE_SHORT_PAYLOADS_ONLY is not set
# CONFIG_ESP_MODEM_ADD_CUSTOM_MODULE is not set
CONFIG_ESP_MODEM_C_API_STR_MAX=128
# CONFIG_ESP_MODEM_URC_HANDLER is not set
# CONFIG_ESP_MODEM_PPP_ESCAPE_BEFORE_EXIT is not set
# CONFIG_ESP_MODEM_ADD_DEBUG_LOGS is not set
# end of esp-modem
# end of Component config
When there is little or no PPP activity or not using CMUX, the response to AT+CMUX returned from dce->at() looks like:
+CPSI: LTE,Online,310-410,0x830B,79778826,148,EUTRAN-BAND2,700,5,5,116,1043,727,16
But when in CMUX mode with PPP activity, we only receive:
8,EUTRAN-BAND2,700,5,5,116,1043,727,16
Seems to always drop the first 44 bytes.