ESP Modem component CMUX example not working

[skateone]

Good day.
I am trying to get your esp modem component working with my SIMCOM A 7672E modem.
my requirement is to be able to CMUX gps AT commands while handling an active PPPos connection with the ESP32C3 SOC.


compent URL : https://components.espressif.com/compon ... /esp_modem

The example doesnt work...

i have neabled the debug log on the standard CMUX example provided :

D (844) intr_alloc: Connected src 39 to int 2 (cpu 0)
I (849) sleep: Configure to isolate all GPIO pins in sleep state
I (856) sleep: Enable automatic switching of GPIO sleep configuration
D (863) cpu_start: Setting C++ exception workarounds.
D (868) intr_alloc: Connected src 50 to int 3 (cpu 0)
I (873) cpu_start: Starting scheduler.
D (877) intr_alloc: Connected src 37 to int 4 (cpu 0)
D (877) heap_init: New heap initialised at 0x3fcc0000
D (877) intr_alloc: Connected src 33 to int 7 (cpu 0)
D (887) event: running task for loop 0x3fc95c50
D (887) event: created task for loop 0x3fc95c50
D (887) event: created event loop 0x3fc95c50
D (897) esp_netif_lwip: LwIP stack has been initialized
D (897) esp_netif_lwip: esp-netif has been successfully initialized
I (25907) uart: queue free spaces: 30
D (25907) intr_alloc: Connected src 22 to int 9 (cpu 0)
D (25907) esp_netif_objects: esp_netif_add_to_list 0x3fc9b0cc
D (25907) esp_netif_objects: esp_netif_add_to_list netif added successfully (total netifs: 1)
D (25917) esp-netif_lwip-ppp: esp_netif_new_ppp: PPP connection created: 0x3fc9b3fc
D (25927) esp-netif_lwip-ppp: Phase Dead
D (25927) command_lib: generic_command command AT+CMUX=0

D (25937) command_lib: Response: AT+CMUX=0
OK

D (25947) CMUX: Payload frame: dlci:00 type:73 payload:0 available:2
D (25957) CMUX: Payload frame: dlci:01 type:73 payload:0 available:2
D (25967) CMUX: Payload frame: dlci:02 type:73 payload:0 available:2
D (25977) command_lib: generic_command command ATE0

D (25977) CMUX: Payload frame: dlci:01 type:ef payload:5 available:19
D (25977) CMUX: Payload frame: dlci:01 type:ef payload:6 available:8
E (26477) cmux_example: Failed to configure desired mode... exiting
D (26477) event: deleted loop 0x3fc95c50

[rpiloverbd]

Hi, I think you'll get more help if you share your connection diagram.

[skateone]

The modem connections are custom but i have changed the example source to cater for that.
here goes:

Modem reset IO9. ( this is the boot pin i know but it works well for modem reset )
Modem Power: IO5

IO9 and IO5 drive grounding mosfets that act as switches

MOdem Status : IO6 ( feedback from modem to esp32c3 formodem power status )
Modem TXD: IO7
Modem TXD: IO10

TX and TX pass through a 3.3V to 1.8V bidirectional Voltage translator

If you look at the logs the modem powers up and get access to the AT interface. all the other exemples work fine..
Just not the CMUX

[skateone]

an update:

i have been testing with the terminal example app...

from what i can see the unit goes into cmux mode but then after that the response times out..

cmux init log

I (39897) modem_console: Switching to CMUX name...
D (39897) command_lib: generic_command command AT+CMUX=0

] (39898) TERM: starting cmd transaction [AT+CMUX=0
D (39918) DATA RECEIVED: 0x3fc9e414 41 54 2b 43 4d 55 58 3d 30 0d 0d 0a 4f 4b 0d 0a |AT+CMUX=0...OK..|
D (39919) command_lib: Response: AT+CMUX=0
OK


D (39932) CMUX Received: 0x3fc9e414 f9 03 73 01 d7 f9 |..s...|
D (39933) CMUX: Payload frame: dlci:00 type:73 payload:0 available:2
D (39951) CMUX Received: 0x3fc9e414 f9 07 73 01 15 f9 |..s...|
D (39952) CMUX: Payload frame: dlci:01 type:73 payload:0 available:2
D (39971) CMUX Received: 0x3fc9e414 f9 0b 73 01 92 f9 |..s...|
D (39972) CMUX: Payload frame: dlci:02 type:73 payload:0 available:2
I (39990) modem_console: OK


cmux enabled with AT sent:

I (218315) modem_console: Sending command AT with timeout 1000
] (218316) TERM: starting cmd transaction [AT
I (218317) TERM CMUX: set read callback
D (218328) Send: 0x3fc9fd08 f9 05 ef 07 |....|
D (218329) Send: 0x3fc9fe18 41 54 0d |AT.|
D (218340) Send: 0x3fc9fd0c b2 f9 |..|
D (218337) CMUX Received: 0x3fc9e414 f9 05 ef 07 41 54 0d b2 f9 f9 05 ef 0d 0d 0a 4f |....AT.........O|
D (218363) CMUX Received: 0x3fc9e424 4b 0d 0a 5f f9 |K.._.|
D (218364) CMUX: Payload frame: dlci:01 type:ef payload:3 available:17
D (218375) CMUX: Payload frame: dlci:01 type:ef payload:6 available:8
I (219351) TERM CMUX: set read callback
E (219351) modem_console: Failed with TIMEOUT


The repsonse from the modem is correct but seems like the callback functions are not triggereing corredctly and then we incure a timeout

[akabhinav32]

I have the same use case, the same SIMCOM chip, and the same problem. Could you find a solution to the problem?

Thanks

[skateone]

i wrote my own cmux handler but its still has lots of bugs. want to attemt the new realease.. will let you know on the outcome of that