Teensy and differential inputs/outputs (hooking DisplayPort AUX CH)

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TnF

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Hello. I started a personal project where i design a device that includes these 2 functions:

1) Read/Sniff the EDID data of a DisplayPort downsteam device (i.e. a PC monitor)
2) Send/Emulate the EDID data to the upstream device (i.e. a GPU)

While i thought i could use an AVR board to do this (i.e. ATmega32U4), i've just changed my mind because i think the limitations make it more difficult that it needs to be.
So i think a Teensy LC/3.2/4.0 is a better choice (in fact i have all 3 at home ready to use anytime; i always keep one of each in "stock" just for such sudden projects 😂)

From what i understand so far EDID data on Displayport are transmitted via the AUX Differential Pair channel of which has 2 available modes for operation (page 329):
- 1Mbps stream Manchester-II code
- 720Mbps stream FAUX 8B10B encoding

For snooping, i plan on hooking to the AUX CH via a dedicated differential pair input (of which i hope the Teensy's have on chip since i haven't checked the datasheet yet).
Still i'm not sure if the input impedance will have any negative effects.

Now for the output i am completely unsure of the suitability of the controllers and which pins would be acceptable to use.

So my question is which teensy should be suitable in terms of processing speed in order to sample and decode the signal, and to be able to generate and output a 1Mbps Manchester-II code differential signal.

Maybe i'll need to use a kind of dedicated driver or decoder instead for both cases.

Also if Teensy 3.2 is suitable is there a reason not to use Teensy 4.0 considering they cost the same?


ps. For the AUX CH switching from the monitor to the microcontroller i'll just use a USB switch IC, example the USB3740B i've used in the past which should be suitable

Kind regards

Datasheets:

Displayport v1.2 standard:
https://glenwing.github.io/docs/DP-1.2.pdf

USB3740B:
http://ww1.microchip.com/downloads/en/DeviceDoc/00001725D.pdf
 
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