3 ms·
If anyone knows products that fit this use case, I'd love to know as well.
by heavyset_go 4y ago
If anyone knows products that fit this use case, I'd love to know as well.
- CamperBob2 4y agoFor better or worse, memory-mapped I/O isn't coming back -- how would that work on a modern flat-model OS with memory protection, anyway? It would require dedicated support from the memory controller itself, not something a system OEM could even think about implementing themselves. It also wouldn't be useful for real-time applications, since these machines don't generally run true real-time operating systems. Delegating I/O to a dedicated controller usually makes much more sense than trying to do it by bit-banging ports (or addresses) on a general-purpose CPU running a general-purpose OS. Not advocating the Arduino model necessarily, but if you want memory-mapped I/O, my guess is you really want an FPGA connected via PCIe, or at least USB HS. And if you don't need an FPGA to handle your I/O tasks, then there's a darned good chance that the Arduino is actually good enough. What might be interesting is integrating something like a Teensy 4, so that you could offload not only I/O but a non-trivial amount of processing on the data to be acquired or transmitted.
- qhwudbebd 4y agoI'm probably describing what I want incorrectly with 'memory mapped IO'. All I'm after is GPIO, SPI and I2C directly attached to the real processor, as you get with a completely standard Raspberry Pi or Rockchip board, but apparently never on x86.
- heavyset_go 4y agoAll I want is a card or motherboard with some GPIOs and other pins. I've seen some products that almost get there, but they're something awkward like an ARM SBC stuck on Linux 2.6.x with an embedded Arduino. Memory mapping doesn't matter to me, although it would be cool.