3 ms·

Yes but our default USB HID stack isn't made for it. USB is not good for sub millisecond latency. If you make a keyboard that can send signals fast-clocked ove

• bluescrn 3y ago
  ‘Input lag’ in games is rarely about input. It’s usually all about the latencies involved in getting graphics onto the screen after responding to the input. Even an FPGA-based ‘emulator’ or real retro hardware with the fanciest low-latency upscaler won’t feel truly responsive if connected to an LCD TV that adds 60-100ms of latency (yes, some are really that bad, especially if not in ‘game mode’)
  • zare_st 3y ago
    Agreed. I might've put "human interface" as opposed to HID, to cover the output too. We didn't design modern stacks to handle lowest latencies possible. Because everything is a tradeoff. Take a look at audio I/O on normal PC in 2000s. Although input digitizing and output de-digitizing were always fast enough, the "DSP" (moving data to userspace, processing, and out) was slow. Because in software design it was given that millisecond latencies aren't a thing, we used a lot of locks and copying around to ensure the system works correctly for average use which isn't realtime IO. However when someone desired realtime IO they enhanced the drivers and/or the audio software stack. That approach worked because there were no issues in electronics, so to speak. With gaming you have slow USB input and slow HDMI/whatever output. In my view that is peripheral issue and not architecture issue, although you can also say it is a platform issue. The question is not that straightforward.