PCjr Ethernet Adapter

[dpaden]

So I searched around on the forums and saw quite a lot of interest in networking the PCjr. It looks like there were 2 main directions related to Ethernet connectivity:
viewtopic.php?f=1&t=607
and
viewtopic.php?f=1&t=635&p=4872

I was curious if anyone was still working on the former.

I have experience working with wired Ethernet directly on ST microcontrollers (with embedded MACs). I was thinking the bus interface on the jr is slow enough that I could directly interface the 8-bit bus with GPIO to emulate the parallel bus. then I'd need to work out a packet driver. However, the RPi thing looks pretty sweet and that might work out pretty good already.

I figured I could mechanically fit the RJ45 jack in the modem slot (have to rotate that jack 90 deg. as mentioned in the first post), but it has the nice benefit that you don't need to purchase any old connectors.
Is anyone interested in this?

I am a little concerned about the low clock provided to the modem port (1.7MHz according to the ref. manual)...are we getting a full speed bus to the modem port?

Is anyone interested in this kind of solution? The ST CPU and PHY BOM should beat the price of the wiznet part...but then there's ordering PCBs to put the parts on. Also, the ST CPUs generally have default MAC addresses built in, if I recall right. Later down the road, we could interface the CPU to an ST (or other vendor) WiFi module to add in Wifi. Since there'd be a new packet driver, we can add a few hooks to the command line to set the SSID and encryption keys as needed.

[dpaden]

I am interested in the -IOR, -IOW, and how the DIR pin of the data bus driver gate is driven.
Does anyone have a timing diagram of the IO bus? Or is there one in the ref manual?

I can tap the lines and measure them if no one has this information easily accessible.

[dpaden]

If someone has a timing diagram it would be nice, but I think I understand it from reading the descriptions in the IO bus section now.