4 ms·
> However it wasn't fast (23 kB/s IIRC) and it completely bogged down the host (no hardware acceleration there). In the most basic fallback mode, the "uplink"
by retrac 5y ago
> However it wasn't fast (23 kB/s IIRC) and it completely bogged down the host (no hardware acceleration there).
In the most basic fallback mode, the "uplink" from device to host is actually working 4 bits at a time over the "control" lines. All polled with no interrupts. The driver spends most of its time in a busy loop.
The parallel port eventually did eventually get quite fancy in the 90s, with buffered, interrupt-driven bidirectional communication possible in ECP mode (~2 MB/s). But USB was already on the rise by then and it was basically obsolete by the time drivers and motherboards widely supported it.
- u801e 5y agoIIRC, you could only utilize ECP mode with a laplink brand cable (which would give you the faster transfer rate). Otherwise, you had to use EPP. I used the latter with a regular parallel cable with an adaptor I soldered with a certain pin to pin configuration.
- LargoLasskhyfv 5y agoIt depended on the quality of the IO-chipset on your board, or cards. I remember experimenting with that between 91 to 94, and got it up to 4Mbit/s via parallel with ECP/EPP-DMA something. I also used something looking exactly like this http://www.cablesonline.com/rsdbbreakbox.html http://www.cablesonline.com/rsdbbreakbox.html with gender changers. Imagine the red/green blinkenlights! But that was mostly just for fun, I already had Ethernet.