My project requires that I write a from-scratch driver for the CC3100. I'm using the CC3100 Booster Pack and directly communicating over SPI to an 8-bit MCU. When my driver attempts to establish a TCP connection using a SOCK_STREAM socket, an error of -145 (SL_ESEC_ASN_TAG_NULL_E) is returned. The relevant message sequence is as follows.
All message byte values are in HEX:
Connect TCP port 80 to openweathermap.org
-----------------------------------------
06 94 SL_OPCODE_SOCKET_CONNECT
0C 00 message length
00 00 padding
10 socket number
20 family and flags
00 50 port 80, high byte first.
CC CC padding
90 4C 66 A6 IPv4 address
After about a 10-second delay, the following is returned:
---------------------------------------------------------
06 10 SL_OPCODE_SOCKET_CONNECTASYNCRESPONSE
08 00 message length
17 01 01 00 flow control
91 FF status 0xFF91 = -145
10 socket
00 padding
-145 is defined in socket.h as SL_ESEC_ASN_TAG_NULL_E, "ASN tag error, not null". Its name and description suggest an ASN.1 error. That specification is closely associated with the use of public keys. In the CC3100 circumstance, this would have to be either SSL or TLS.
However, the socket was established with (SL_SOCK_STREAM, SL_IPPROTO_TCP) arguments, vs. (SL_SOCK_STREAM, SL_SEC_SOCKET). Further, a socket request using the latter arguments returns 80 as the socket identifier.
What causes this CC3100 behavior?
Where is this behavior documented?
