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hcContLen in the ELS-31V and the PLS62W and more than 1500 byte writes | Telit Cinterion IoT Developer Community

March 7, 2020 - 8:40pm, 1548 views

I am trying to send a ~50K picture .jpg and have run into the 1,500 byte limit per SISW operation.  According to the AT commands description for SISS where hcContLen is defined, it can be defined up to 2^31-1 as the Http post size.  When I assign a value of, for example, 99999, it will only display "9999", limiting it to 4 digits.  So my questions are as follows.  Is the value that entered correct or is hccontlen limited to 9999?

Actual output after doing:

at^siss=0,hccontlen,99999

^SISS: 0,"cmd","post"
^SISS: 0,"hcContent"," "
^SISS: 0,"hcContLen","9999"
^SISS: 1,"srvType","Http"
^SISS: 1,"conId","3"
^SISS: 1,"alphabet","1"

Second Question: Once I set hccontlen to a value greater than 1500 (for example: 99999), do I execute multiple at^sisw=0,1500,1 to write more than 1500 bytes?  I read something about "chunk encoding" on the http layer, so I am assuming that I can do multiple writes until I reach my hccontlen length of 99999.

Thank you, kinda stuck here!

Allan Overcast

Tracer Technology Systems, Inc.