Micropython PPP - ESP32 peers

[jouellnyc]

Good Day Micropythoner's

I've setup 2 ESP32s (w/spiram) devices via UART. I have done this direct from esp32 to esp32 with a simple jumper and also using rs-422 modules. Life it great in terms of sending data from 1 to the other.

I was trying to see if I could get a peer PPP session between the two and ping the other's IP address from one to the other. (I did this with some rasp pi zeros, so wanted to see if I could do so with esp32's). Is that possible with micropython and the esp32's?

It seems like it could since I understand PPP was implemented in MP for esp32 but I'm not sure -- it seems like mostly people are using if for modem connections/etc.

Here's as far as I got. I seem not to be able to assign IPs to the esp32's:

#contents of set_ppp.py
import network
import machine
uart = machine.UART(2, baudrate=9600, tx=13, rx=14)
ppp = network.PPP(uart)
ppp.active(True)
ppp.connect()
ppp.ifconfig(('192.168.0.2', '255.255.255.0', '192.168.0.1', '8.8.8.8'))
ppp.ifconfig()

MicroPython v1.22.2 on 2024-02-22; Generic ESP32S3 module with Octal-SPIRAM with ESP32S3
Type "help()" for more information.

>>> import set_ppp
>>> set_ppp.ppp.ifconfig()
('0.0.0.0', '0.0.0.0', '255.255.255.255', '8.8.8.8')     <===Shouldn't I be able to set my own IP address?

If I switch connect() and infconfig() around it does not seem to help. I will soon try to connect an esp32 to a rasp pi zero as well, but for now am trying as stated.

Many thanks in advance!

[jouellnyc]

A bit of an update:

• I am able to get an ESP32 and a raspberry pi zero to communicate via their serial port just fine.

And some background:

• If I configure the pi zero as the 'ppp server' like https://github.com/jouellnyc/UART/tree/main/pizero_simple:

stty -F /dev/ttyAMA0 raw
pppd /dev/ttyAMA0 1000000 10.0.5.1:10.0.5.2 proxyarp local noauth debug nodetach dump nocrtscts passive persist maxfail 0 holdoff 1

I can get 2 ri pizeros to establish a ppp session perfectly.

When I try with the esp32 as the client, it never establishes the ppp session, but again data ("Hello PI/ Hello World") transfers just fine.

Either I don't quite have the esp32 side ppp commands correct or perhaps there are some limits with respect to the esp32 ppp implementation?

[rkompass]

There were a few commits yesterday e.g. this one for enabling ipconfig of PPP.

Perhaps you need that.?

[jouellnyc]

Thank you @rkompass for the heads up and reply! I am guessing that would make it into a preview build. I'll look in to pursing this.

[jouellnyc]

Interesting. Both

v1.24.0-preview.23.g8809ae716 and v1.24.0-preview.10.gc1a6b95bf are working.

I am sharing some more details in case someone else happens upon this (sometimes it's good to have a reference of a good outcome):

=== PICO

>>> import machine
>>> import time
>>> uart = machine.UART(2, baudrate=9600, tx=13, rx=14)
>>> import network
>>> ppp = network.PPP(uart)
>>> ppp.active(True)
True
>>> ppp.connect()            <=== connection happens!
>>> ppp.isconnected()
True
>>> 
>>> ppp.ifconfig()
('10.0.5.2', '10.0.5.1', '255.255.255.255', '8.8.8.8')

=== PI ZERO 

root@pizero1wa:~# pppd /dev/ttyAMA0 9600 10.0.5.1:10.0.5.2 proxyarp local noauth debug nodetach dump nocrtscts passive persist maxfail 0 holdoff 1
pppd options in effect:
debug		# (from command line)
nodetach		# (from command line)
holdoff 1		# (from command line)
persist		# (from command line)
maxfail 0		# (from command line)
dump		# (from command line)
noauth		# (from command line)
/dev/ttyAMA0		# (from command line)
9600		# (from command line)
lock		# (from /etc/ppp/options)
nocrtscts		# (from command line)
local		# (from command line)
asyncmap 0		# (from /etc/ppp/options)
passive		# (from command line)
lcp-echo-failure 4		# (from /etc/ppp/options)
lcp-echo-interval 30		# (from /etc/ppp/options)
hide-password		# (from /etc/ppp/options)
proxyarp		# (from command line)
10.0.5.1:10.0.5.2		# (from command line)
noipx		# (from /etc/ppp/options)
using channel 7
Using interface ppp0
Connect: ppp0 <--> /dev/ttyAMA0
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x76d069a0> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x76d069a0> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x76d069a0> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x76d069a0> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x76d069a0> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x76d069a0> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x76d069a0> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x76d069a0> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x76d069a0> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x76d069a0> <pcomp> <accomp>]
**rcvd [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0xe326a67> <pcomp> <accomp>]            <====ppp.connect()**
sent [LCP ConfAck id=0x1 <asyncmap 0x0> <magic 0xe326a67> <pcomp> <accomp>]
rcvd [LCP ConfAck id=0x1 <asyncmap 0x0> <magic 0x76d069a0> <pcomp> <accomp>]
sent [LCP EchoReq id=0x0 magic=0x76d069a0]
sent [CCP ConfReq id=0x1 <deflate 15> <deflate(old#) 15> <bsd v1 15>]
sent [IPCP ConfReq id=0x1 <compress VJ 0f 01> <addr 10.0.5.1>]
sent [IPV6CP ConfReq id=0x1 <addr fe80::4525:063a:936d:d365>]
rcvd [LCP ConfAck id=0x1 <asyncmap 0x0> <magic 0x76d069a0> <pcomp> <accomp>]
rcvd [LCP ConfAck id=0x1 <asyncmap 0x0> <magic 0x76d069a0> <pcomp> <accomp>]
rcvd [LCP ConfAck id=0x1 <asyncmap 0x0> <magic 0x76d069a0> <pcomp> <accomp>]
rcvd [IPCP ConfReq id=0x1 <compress VJ 0f 01> <addr 0.0.0.0> <ms-dns1 0.0.0.0> <ms-dns2 0.0.0.0>]
sent [IPCP ConfRej id=0x1 <ms-dns1 0.0.0.0> <ms-dns2 0.0.0.0>]
rcvd [IPV6CP ConfReq id=0x1 <addr fe80::28f2:63c7:9b25:65c6>]
sent [IPV6CP ConfAck id=0x1 <addr fe80::28f2:63c7:9b25:65c6>]
rcvd [LCP EchoRep id=0x0 magic=0xe326a67]
rcvd [LCP ProtRej id=0x2 80 fd 01 01 00 0f 1a 04 78 00 18 04 78 00 15 03 2f]
Protocol-Reject for 'Compression Control Protocol' (0x80fd) received
rcvd [IPCP ConfAck id=0x1 <compress VJ 0f 01> <addr 10.0.5.1>]
rcvd [IPV6CP ConfAck id=0x1 <addr fe80::4525:063a:936d:d365>]
local  LL address fe80::4525:063a:936d:d365
remote LL address fe80::28f2:63c7:9b25:65c6
Script /etc/ppp/ipv6-up started (pid 1222)
rcvd [IPCP ConfReq id=0x2 <compress VJ 0f 01> <addr 0.0.0.0>]
sent [IPCP ConfNak id=0x2 <addr 10.0.5.2>]
Script /etc/ppp/ipv6-up finished (pid 1222), status = 0x0
rcvd [IPCP ConfReq id=0x3 <compress VJ 0f 01> <addr 10.0.5.2>]
sent [IPCP ConfAck id=0x3 <compress VJ 0f 01> <addr 10.0.5.2>]
Script /etc/ppp/ip-pre-up started (pid 1224)
Script /etc/ppp/ip-pre-up finished (pid 1224), status = 0x0
Cannot determine ethernet address for proxy ARP
local  IP address 10.0.5.1
remote IP address 10.0.5.2
Script /etc/ppp/ip-up started (pid 1227)
Script /etc/ppp/ip-up finished (pid 1227), status = 0x0

So now honestly speaking, I had a bunch of problems, which I thought I resolved one by one, which may not have been true, Now that I see the ppp.connect() sending data across I believe it was a line speed mismatch that I corrected (stty command on the pi side) .
And since I didn't really know how ppp was working per se, I was not sure what was off... So thanks again!

[jouellnyc]

Also a separate note: Everything works without the esp32 needing to call ppp.ifconfig(()) to set anything at all. It picked up the details from the 'server'.