AT+CCHO not working in WP7611

IoT Modules WP Series
1

WP7611 can’t establish SIM logic channel to eUICC application (ISD-R)

I am using a mangohRED board with a WP7611 populated in it.

I am using lpac (a local profile assitant written in C) -GitHub - estkme-group/lpac: C-based eUICC LPA to access an eUICC (in this case it is a plastic based eUICC from esim.me inserted into the SIM slot not a solderable one!)

I managed to get lpac working with MC7455 and EM7590 using its AT driver.

Unfortunately it doesn’t work with WP7611 since it fails opening a logic channel to the eUICC:

$ sudo AT_DEBUG=1  LPAC_APDU=at AT_DEVICE=/dev/ttyUSB2 ./lpac profile list
AT_DEBUG: AT+CCHO=?
AT_DEBUG: OK
AT_DEBUG: AT+CCHC=?
AT_DEBUG: OK
AT_DEBUG: AT+CCHO="A0000005591010FFFFFFFF8900000100"
AT_DEBUG: +CME ERROR: Parameters error

If I set AT+CMME=1 it shows this as error 323

Any idea of what might be the issue? same card works with MC7455 and EM7590

Some more information

ATI
Manufacturer: Sierra Wireless, Incorporated
Model: WP7611
Revision: SWI9X07Y_02.37.03.00 73df45 jenkins 2020/04/08 10:59:14
IMEI: 355882100565342
IMEI SV: 14
FSN: 72415126341310
+GCAP: +CGSM,+DS,+ES

OK
AT!CUSTOM?
!CUSTOM:
             GPSENABLE          0x01
             GPSLPM             0x01
             IPV6ENABLE         0x01
             SIMHOTSWAPDIS      0x02
             SIMLPM             0x01
             USBSERIALENABLE    0x01
             SINGLEAPNSWITCH    0x01
             TXONINDICATION     0x01
             HSICENABLE         0x01
             SCRUBEN            0x01
             EXTUIMSWITCHEN     0x01
             EXTGPSLNAEN                0x01

OK
AT+CPIN?
+CPIN: READY

OK
2

AT+CSIM works (but AT+CSIM is less preferable as it doesn’t work unless there is a profile in eSIM):

AT+CSIM=42, "01A4040010A0000005591010FFFFFFFF8900000200"
+CSIM: 4,"611A"

OK
AT+CSIM=10,"81CA005A00"
+CSIM: 40,"5A10890440451167274948000000086327129000"

OK

Also see status file running this script

status__20240812_091203.txt (3.7 KB)

3

After talking to @elkanam seems the bug is that AT+CCHO doesn’t work with "

Verified:

AT+CCHO=A0000005591010FFFFFFFF8900000200
+CCHO: 0000000078d70f5f
OK

AT+CGLA=78d70f5f,10,"81CA005A00"
+CGLA: 40,"5A10890440451167274948000000086327129000"
OK

This is clearly a bug (supported on EM7590, MC7455 and Quectel EC25 as far as my testing goes) I would at least update the documentation about this.

1 Like
4

Seems like profile listing with lpac now works (with patching at.c to not use " for AT+CCHO).

$ sudo AT_DEBUG=1   LPAC_APDU=at AT_DEVICE=/dev/ttyUSB2 ./lpac profile list 
AT_DEBUG: AT+CCHO=?
AT_DEBUG: OK
AT_DEBUG: AT+CCHC=?
AT_DEBUG: OK
AT_DEBUG: AT+CCHO=A0000005591010FFFFFFFF8900000100
AT_DEBUG: +CCHO: 0000000078ca3b3f
AT_DEBUG: 
AT_DEBUG: OK
AT_DEBUG: AT+CGLA=78ca3b3f,16,"81E2910003BF2D00"
AT_DEBUG: +CGLA: 4,"613C"
AT_DEBUG: 
AT_DEBUG: OK
AT_DEBUG: AT+CGLA=78ca3b3f,10,"81C000003C"
AT_DEBUG: +CGLA: 124,"BF2D39A037E3355A0A981321010000101912074F10A0000005591010FFFFFFFF89000010009F700101910654656C6E7978920654656C6E79789501029000"
AT_DEBUG: 
AT_DEBUG: OK
{"type":"lpa","payload":{"code":0,"message":"success","data":[{"iccid":"XXXXXXXXX","isdpAid":"a0000005591010ffffffff8900001000","profileState":"enabled","profileNickname":null,"serviceProviderName":"XXXX","profileName":"XXXX","iconType":null,"icon":null,"profileClass":"operational"}]}}
AT_DEBUG: AT+CCHC=78ca3b3f
AT_DEBUG: OK

Replaced some info with XXXX

1 Like
5

Need to be careful if not closing the previous session and trying to open a new session, it will break AT+CCHO until AT!RESET:

AT_DEBUG: AT+CCHO=?
AT_DEBUG: OK
AT_DEBUG: AT+CCHC=?
AT_DEBUG: OK
AT_DEBUG: AT+CCHO=A0000005591010FFFFFFFF8900000100
AT_DEBUG: +CCHO: 0000000078ca403f
AT_DEBUG: 
AT_DEBUG: OK
AT_DEBUG: AT+CGLA=78ca403f,16,"81E2910003BF2D00"
AT_DEBUG: +CGLA: 4,"6D00"
AT_DEBUG: 
AT_DEBUG: OK
1 Like