Well, we are currently connecting to the controller port because it's really easy to connect to those. But of course you can only hammer at those registers at around 40KB/s.
So yeah, a friend made a PCB and found some female edge connectors we can cut to size to connect to the EXT port, where we can DMA at 2.68MB/s through using eight data lines. On the other side of the PCB, we just stuck a custom sized 28-pin IDE header. Easy to do whatever with that: wire to breadboard one-at-a-time or with an IDE cable.
The hope would be to then have some device that monitors each clock rise, grab the eight bits on the data bus, and send it to the PC. It can buffer a bit and have some latency, that's not a big deal.
But even with ICs that can latch the data quickly enough, we don't have enough bandwidth over serial nor USB1 to send 2.68MB/s of data. It'll have to be high-speed USB2, and will almost certainly need to be some kind of custom driver, as I doubt you can do some kind of super baud-rate of 16,000,000+bps.
> It'll have to be high-speed USB2, and will almost certainly need to be some kind of custom driver, as I doubt you can do some kind of super baud-rate of 16,000,000+bps
The venerable FT232H claims "data transfer speeds up to 40Mbytes/s":
I'm not sure what is needed to actually accomplish such rates. Might be easier to do it with USB-enabled MCU. Either way, I wouldn't discount the standard USB classes too early. I'm "pretty sure" that you should be able to push some tens of Mbps through USB-CDC class.
So yeah, a friend made a PCB and found some female edge connectors we can cut to size to connect to the EXT port, where we can DMA at 2.68MB/s through using eight data lines. On the other side of the PCB, we just stuck a custom sized 28-pin IDE header. Easy to do whatever with that: wire to breadboard one-at-a-time or with an IDE cable.
The hope would be to then have some device that monitors each clock rise, grab the eight bits on the data bus, and send it to the PC. It can buffer a bit and have some latency, that's not a big deal.
But even with ICs that can latch the data quickly enough, we don't have enough bandwidth over serial nor USB1 to send 2.68MB/s of data. It'll have to be high-speed USB2, and will almost certainly need to be some kind of custom driver, as I doubt you can do some kind of super baud-rate of 16,000,000+bps.