mbed assertation failed: iface, file: ./main.cpp, line 228

[dlfryar-zz]

Out of the box build results in mbed assertation failed: iface, file: ./main.cpp, line 228

Updated mbed_app.json to add trace and debug

Updated main.cpp to add a 20 second wait after the dot_thread.start() which results in a HardFault.

Crash Info:
	Crash location = dot_event() [0x000017E0] (based on PC value)
	Caller location = osDelay [0x00003FD1] (based on LR value)
	Stack Pointer at the time of crash = [20003C40]
	Target and Fault Info:
		Processor Arch: ARM-V7M or above
		Processor Variant: C24
		Forced exception, a fault with configurable priority has been escalated to HardFault
		A precise data access error has occurred. Faulting address: 20030068

Tried with the following hardware:

• Gemalto Cinterion Connect Shield
• NXP FRDM-K64F
• Avnet AT&T WNC 14A2A Cellular IoT Kit

Gemalto direct AT configuration

OK
ati1
Cinterion
ELS61-US
REVISION 01.000
A-REVISION 00.026.00
 
OK
at+cops=?
+COPS: (2,"AT&T","AT&T","310410",7),(1,"AT&T","AT&T","310410",2),(1,"","","313100",7),(1,"T-Mobile","T-Mobile","310260",2))
 
OK
at+cops?
+COPS: 0,0,"AT&T",7
 
OK
at+creg?
+CREG: 0,1
 
OK
at+cgdcont?
+CGDCONT: 1,"IP","m2m.com.attz.mnc170.mcc310.gprs","",0,0
 
+CGDCONT: 3,"IP","BROADBAND","",0,0
 
OK

main.cpp.txt
mbed_app.json.txt
capture-2018-06-18-001.txt

[dlfryar-zz]

cc: @AriParkkila

[ciarmcom]

ARM Internal Ref: IOTCELL-1111

[AriParkkila]

@dlfryar thanks for good logs.

1. Assert is expected as K64F does not have hosted cellular module. You seem to be using K64F + Gemalto ELS61 module so you need to add this in the mbed_app.json:

   "macros": ["CELLULAR_DEVICE=GEMALTO_ELS61", "MDMRXD=D0", "MDMTXD=D1"]

2. You need to define also "mbed-trace.enable": true or update to mbed-os-master because we are missing some debug commits on the mbed-os-5.9 branch.

3. Example seems to have a bug in dot_event() which does not check that iface is created before using it. We need to fix that.

[dlfryar-zz]

Here's another run with the recommended changes:

mbed_app.json.txt

Copy Gemalto drivers from ciot-example

cp -R ciot-example/source/cellular/targets/GEMALTO mbed-os-example-cellular/
mbed-os/features/cellular/framework/targets

Build syntax

cd mbed-os && git pull && mbed update master && cd ..
mbed compile -t GCC_ARM -m K64F

Error output

mbed-os-example-cellular
Establishing connection

.

++ MbedOS Error Info ++
Error Status: 0x80010130 Code: 304 Module: 1
Error Message: could not pinout
Location: 0x183a7
Error Value: 0x1009
Current Thread: Id: 0x2000da0c Entry: 0x18ee1 StackSize: 0x1000 StackMem: 0x2000da58 SP: 0x2000e988 
-- MbedOS Error Info --


mbed-os-example-cellular
Establishing connection

.

++ MbedOS Error Info ++
Error Status: 0x80010130 Code: 304 Module: 1
Error Message: could not pinout
Location: 0x183a7
Error Value: 0x1009
Current Thread: Id: 0x2000da0c Entry: 0x18ee1 StackSize: 0x1000 StackMem: 0x2000da58 SP: 0x2000e988 
-- MbedOS Error Info --

[dlfryar-zz]

One additional datapoint is that I have not been able to validate hardware flow control working with the Gemalto module. Configuring "MDMRTS=D2" and "MDMCTS=D3" does not seem to work as expected. I'm still having to jumper D2 and D3 in order for the board to respond on the AT interface.

[AriParkkila]

@dlfryar there seems to be a NULL pointer crash if APN lookup is enabled. We will fix this immediately. ARM internal ref IOTCELL-1122

I don't actually know which pins should be defined on K64F as RTS/CTS?

[AriParkkila]

@dlfryar I think this can be closed as the both crash fixes are now merged, please see:

• Cellular: fixed defect where SIM interface was closed too early mbed-os#7275
• ecf43d8

I guess you need to bridge RTS/CTS pins on Cinterion just the way you have already done.

[dlfryar-zz]

mbed-o

++ MbedOS Error Info ++
Error Status: 0x80010130 Code: 304 Module: 1
Error Message: could not pinout
Location: 0x181d3
Error Value: 0x1009
Current Thread: Id: 0x2000da0c Entry: 0x18d0d StackSize: 0x1000 StackMem: 0x2000da58 SP: 0x2000e988 
-- MbedOS Error Info --

Reran with the same mbed_app.json above and a fresh clone including the copy step for the Gemalto drivers.

build.log

[dlfryar-zz]

I'll work out the RTS/CTS issue once the example builds and runs cleanly. I did learn that the Gemalto Cinterion module has the CTS/RTS pins fixed at D2/D3 so bending the pins and jumper wiring it is necessary.

FRDM-K64F

PTC16 – RX – D0
PTC17 – TX – D1
PTC18 – RTS – J6 pin 8
PTB9 – CTS – D2

[dlfryar-zz]

@AriParkkila can you test with the K64F + Cinterion shield then with the NRF52840_DK?

[AriParkkila]

@dlfryar thanks for the pin map. That seems to work, but note that you need to use K64F pin PTC18 in configuration:
"macros": ["CELLULAR_DEVICE=GEMALTO_ELS61", "MDMRXD=D0", "MDMTXD=D1", "MDMRTS=PTC18", "MDMCTS=D2"]

I tried that on both Cinterion EVB and Connect Shield. It seems that my connect shield does not need RTS/CTS to be bridged at all, but it's enough to connect TX/RX.

Also NRF52840_DK EVB seems to work fine with RS232 shield (without RTS/CTS) when wired to Connect Shield:
"macros": ["CELLULAR_DEVICE=GEMALTO_ELS61", "MDMRXD=D0", "MDMTXD=D1"]

[dlfryar-zz]

Verified assertion is resolved with latest release.