Hi, I would like to know the maximum number of packets that the 9160 modem can cache when sending over TCP. Also, is there any documentation on the 9160 modem?
Thanks!
Hi, I would like to know the maximum number of packets that the 9160 modem can cache when sending over TCP. Also, is there any documentation on the 9160 modem?
Thanks!
Hi,
May I ask why you want to know this?
If the buffer in the modem is full, a call to send() will block, until there is enough space available.
Also, is there any documentation on the 9160 modem?
What exactly are you looking for?
You can find some documentation here: https://infocenter.nordicsemi.com/topic/ps_nrf9160/ip/radio_lte/doc/frontpage.html
There is also some information in the AT command guide: https://infocenter.nordicsemi.com/topic/ref_at_commands/REF/at_commands/intro.html
The documentation for the modem library also covers some of the features of the modem itself: https://developer.nordicsemi.com/nRF_Connect_SDK/doc/2.3.0/nrfxlib/nrf_modem/README.html
Best regards,
Didrik
May I ask why you want to know this?
If the buffer in the modem is full, a call to send() will block, until there is enough space available.
Hi,
Because I don't want the send() interface to be blocked, i.e. the TCP cache is not used up. I am using MQTT to publish data and wait for an ACK. I would like to publish several packets of data before waiting for an ACK so that I can make maximum use of the TCP cache.
Hi,
Can I know the maximum value of this TCP cache? I can't find it in the document
Thanks
Hi, and sorry for the late reply.
I am trying to find an answer to your question, but I have to check a bit internally first.
One question in the meantime though, do you use TLS?
I hope to have an answer for you soon.
Best regards,
Didrik
Again, sorry for the delay.
The modem doesn't have a separate buffer for TCP. Instead, it just uses the same buffer used for sending data between the application and modem cores.
You can configure the size of this buffer with CONFIG_NRF_MODEM_LIB_SHMEM_TX_SIZE. The default value is 8kB, but you can increase it up to 32kB.
You can also read more about the buffer here: https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrfxlib/nrf_modem/doc/architecture.html#tx-area