RP2 PPP

[shariltumin]

According to the documentation, https://docs.micropython.org/en/latest/library/network.PPP.html#network.PPP

class PPP – create network connections over serial

Currently only the esp32 port has PPP support enabled in the default firmware build. 
PPP support can be enabled in custom builds of the stm32 and rp2 ports by enabling networking support and 
setting MICROPY_PY_NETWORK_PPP_LWIP to 1.

I have been trying but unable to build on rp2.

I am unable to locate the mp_network_ppp_lwip_type referred to in:

extmod/modnetwork.c:    { MP_ROM_QSTR(MP_QSTR_PPP), MP_ROM_PTR(&mp_network_ppp_lwip_type) },

Has anyone managed to build firmware for rp2 or stm32 that supports PPP?

[robert-hh]

Just using MICROPY_PY_NETWORK_PPP_LWIP=1 only works, if there is already LWIP and network support enabled. That does not apply to the RP2_PICO, but the _W models and quite a few other RP2 boards.
mp_network_ppp_lwip_type is defined in extmod/network_ppp_lwip.c.
In addition to ESP32, PP is also enabled by default in the MIMXRT port for boards with already have a network stack enabled.

[shariltumin]

So it seems that my idea to provide nework using PPP for RPI_PICO over ESP32 is flawed and cannot be done.

Thanks anyway.

[robert-hh]

You can enable LWIP and LWIP_PPP on RP2. I considered a similar approach once, since there is a AT firmware for both ESP32 and ESP8266. But it seemed to be tricky to use, and the performance will be poor.

[shariltumin]

Thanks, I will try another approach.

[scruss]

You can enable LWIP and LWIP_PPP on RP2. I considered a similar approach once, since there is a AT firmware for both ESP32 and ESP8266. But it seemed to be tricky to use, and the performance will be poor.

It might be an option for those "Pico" board clones that come with an onboard ESP8266. There is a PPP firmware for the ESP8266, but it's likely a lot of work for a very slow connection. Might be useful for cell modems, though

[robert-hh]

In order to have network.PPP at a plain vanilla RP2, you have to:

• set MICROPY_PY_NETWORK to 1, e.g. in mpconfigboard.h
• set MICROPY_PY_NETWORK_PPP_LWIP, e.g. in mpconfigboard.h
• set(MICROPY_PY_LWIP ON) e.g. in mpconfigboard.cmake
• add require("bundle-networking") to manifest.py

You could make a special board definition as copy of the RP2_PICO board. I compiled it and the firmware shows network.PPP etc. I tested this firmware with a LTE AT type modem and it worked.

[robert-hh]

There is a PPP firmware for the ESP8266

I downloaded this PPP firmware, but did not try to link it to a real board. I think I missed an example for the commands needed to establish a connection.