Wired Ethernet support

[eflukx]

Is there any development going on or planned in this area? If not, what would be best the approach to enable support for wired ethernet in micropyhton?

Some ideas/ponderings:

Would simply wrapping the C API available for wired ethernet (MII) in esp-idf do the job? Is micropython using the tcp/ip stack from the IDF or has it implemented a 'local' network stack (and how would these interact/interfere)? How would using the ethernet API from idf play nicely with the WiFi capabilities available within micropython?

Another possible approach would be to handle the wired connection management in a separate task, outside of the micropython rtos task. Would this be a feasable approach?

A lot of quesitons, but I would like to have a go at obtaining ethernet support from within micropython on the ESP32 one way or the other. Any handles to do so are most welcome!

[MrSurly]

I have a need for this for an upcoming project, and I'd be willing to take on development.

Sounds as if you've already implemented this in C?

I actually have the hardware (ethernet PHY board), bought based on the information found on this page.

[eflukx]

I also have the hardware to play around with this (ESP32-WROOM + lan8720a phy board). I had a go with hooking the hardware up and play around with the ethernet example in the esp-idf.

Edit: Yes I found the same page, with the good work from Frank Sauter. Will mod my PHY board tomorrow. I think first step is to get the hardware working.

Getting this to run in the C/idf world should not be too hard, all hard work (specifically for getting my phy to run with ESP32) seems to be done on the esp-idf source tree already.

How micropython interacts with the esp-idf sdk, specifically the network parts, is unclear to me.

[nickzoic]

G'day Rogier, Yep, the MicroPython API would just wrap the existing ESP-IDF functionality, just cleaning it up a little to make it look more Pythonic. Have a look at the source for "esp32/modnetwork.c" as an example: functions like "esp_active" just wrap the underlying esp_wifi_set_mode function into a form more appropriate for calling from Python. The rest of the networking stack is implemented the same way, eg: "modsocket.c" just wraps underlying ESP-IDF functions as well. The exposed API should be as close as possible to that on other MicroPython platforms so that code is portable cross-platform with minimum pain. I just ordered in a LAN8720 PHY module for testing :-)

[MrSurly]

@nickzoic Are there any other MicroPython platforms that have an ethernet interface?

[eflukx]

Edit: Oops, Misread the question, @MrSurly was asking for _other_ platforms with ethernet. Leaving comment for educational purposes. The ESP32 has an Ethernet MAC on the die. The external interface is called a (R)MII interface, which is a standard interface for ethernet adapters. To obtain a normal (UTP) ethernet interface a 'PHY'-chip and some magnetics (transformers, typically built right into the RJ45 socket) needs to be added. For instance the LAN8720 PHY is supported by the ESP-IDF SDK and can be easily obtained as a module on Ebay for a couple of dollars. In one of the earlier comments on this issue thread, there is a link to a page where it is explained how to hook it all up. Once you've hooked up your PHY board, you have a RJ45 plug to you avail!

[eflukx]

@MrSurly There is a driver for the Wiznet W5500 in the micropyhton source tree (https://github.com/micropython/micropython/tree/master/drivers/wiznet5k).

The Wiznet module provides ethernet as well, but also implements a TCP/IP stack right on the silicon. However, I don't know how this API is exposed in MP.

[MrSurly]

The Wiznet module provides ethernet as well, but also implements a TCP/IP stack right on the silicon. However, I don't know how this API is exposed in MP.

@eflukx I'll look at the source for that one, thanks.

[nickzoic]

Dunno if you'll get a lot from the source ... it's a very different beast ... but the interface once constructed should be mostly interchangable with the WIZNET5K() instance and also the ESP32's existing network.WLAN() instance, that way a programmer can use them interchangeably even if the construction details are different.

[MrSurly]

Okay, I'm moving forward with this. I have the HW working, using the IDF ethernet example.

@nickzoic I'm wondering about proper implementation of the namespace (e.g. network.LAN ? ) and API. Perhaps something like this:

import network
l = network.LAN()
l.init(mdc = machine.Pin(23), mdio = machine.Pin(18), enable = machine.Pin(17), phy_adx = 1) ## set MDC/MDIO/Enable pins and phy address. Probably default all of them to these values.
l.ifconfig() # Same as WLAN
l.mac() # Same as WLAN -- not sure if it can be set
l.isconnected() # If ETH link is detected
l.deinit() # Shutdown 

Also need

[nickzoic]

That would make sense to me: it should provide everything under network.AbstractNIC so that you could easily write code which takes an initted "network.LAN" object or an initted "network.WLAN" object (or even a network.SLIP, for example) and treats them the same.

My hardware still hasn't arrived, but should be here soon ...

[MrSurly]

Ah, okay, hadn't seen network.AbstractNIC yet.

Some pitfalls I found during implementation:

• You have to know your PHY address for the IDF code to work correctly. Both of mine were address 1, using the 8720. The default is 0x1f (31) in sdkconfig. The 8720 can only be 0 or 1, depending on the single address strap pin.
• I have two PHY's. The "official" WaveShare works fine. Another one, which looks similarly built sorta works. The ESP32 can talk to it, and the link comes up, but the DHCP never offer or ack never occurs, so no IP address. I haven't put it on Wireshark yet, but considering the rest of the HW is the same (I have a 14-pin connector), I suspect the module is just crap.

[dpgeorge]

it should provide everything under network.AbstractNIC so that you could easily write code which takes an initted "network.LAN" object or an initted "network.WLAN" object (or even a network.SLIP, for example) and treats them the same.

Yes, exactly!

Calling it network.LAN() sounds good, otherwise network.Ethernet() would be more specific but longer to type (and pretty much all LAN's are Ethernet based anyway).

You have to know your PHY address for the IDF code to work correctly.

Can it be configured dynamically at runtime or must it be done at compile time? If the latter then that's quite limiting...

[MrSurly]

Can it be configured dynamically at runtime or must it be done at compile time? If the latter then that's quite limiting...

Looks like it can be configured at runtime. Yay!

[MrSurly]

WRT network.AbstractNIC support: Does this seem reasonable?

Support

• network.LAN(id = None, mdc = machine.Pin(23), mdio = machine.Pin(18), enable = machine.Pin(17), phy_addr = 1, phy_type = network.PHY_LAN8720) This configures the hardware
• network.active( < is_active > ) Equivalent to ifup or ifdown in Debian parlance
• network.status() Returns a boolean, based on link status
• network.ifconfig( < (ip, subnet, gateway, dns) > )

DO NOT support

Or implement as stubs?

• network.connect()
• network.disconnect()
• network.isconnected() Perhaps also returns link status?
• network.scan()
• network.config()