I too wonder what the speed of such a thing might be. RISCOS comes to mind, as I've been trying to figure a way to do WiFi without the add-on bridge/repeater hardware that's usually suggested, or a second Pi just to do the WiFi. So far I've come up with the idea of using I2C or serial IO to a Photon, but someone who did something similar indicated that the throughput was less than ideal.
This is the Bare metal forum. The request was a lwIP implementation on top of the USB stack.LdB wrote: ↑Tue Sep 26, 2017 6:05 pmWe have been thru all this before the IO speeds are fixed by the GPIO clock speeds
Raspberry Pi 1 of 22.7Mhz, Raspberry Pi 2 of 41.7Mhz and the Raspberry Pi 3 at 65.8Mhz
Subtract away your per packet bits and you would get the maximum possible speeds.
For example if you ran a software UART format 1 start 8 data no parity 1 stop you need 10 bits to get 8 across so the transmission speed is 8/10ths of quoted maximum speed.
You will also struggle to get the Pi2 and Pi3 off the board at those max speeds without a lot of buffering there isn't huge drive available at those speeds.
It is no faster and a heck of a lot more work than just using the onboard USB and Ethernet proper.
Now if you connect two Pi's by Ethernet or USB which will give you around 20Mbs anyhow.
The Pi Zero including the W doesn't have the ethernet port so the USB port supports OTG mode and you directly connect it to another Pi without the tricks around the USB connection for normal Pi's. It's used a fair bit in clusters
http://raspberryjamberlin.de/zero360-pa ... to-a-pi-3/
So there are much simpler options out there that no one would really bother.
See also my previous append with
The Ethernet controller used on the Raspberry Pi is connected to the SoC via USB. So I really need to wait for full USB implementation
Circle (https://github.com/rsta2/circle) has the TCP/IP implementation. The LwIP implementation as discussed here is obslete.LdB wrote: ↑Tue Sep 26, 2017 7:01 pmYou lost me you already gave the linked to circle which I thought had a full USB implementation and a partial Ethernet, they at least show you how to open the special pipe endpoint as I remember?
So do you want me to just connect the Ethernet on it for you to play with. You will see LAN9512 gets enumerated as device 3 I just need to open the special pipe endpoint on that code and select poll, DMA or interrupts method for send receive channels. Device one is my fake hub and device 2 is the real Pi hub. Four and onwards will be whatever else you have plugged into the USB
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