search

fbergama / pigfx

PiGFX is a bare metal kernel for the Raspberry Pi that implements a basic ANSI terminal emulator with the additional support of some primitive graphics functions.
MIT License
275 stars 60 forks source link

PiGFX keyboard TX issues #22

Closed zaphodbe closed 4 years ago

zaphodbe commented 4 years ago

If I load linux on the PI zero the serial port works fine and I can talk to my RC2014, however if I load PiGFX it receives the data from the RC2014 but seems unable to send anything to it.

I tried the normal trick of shorting the TX and RX lines on the Pi to create a loopback and get the same results, works with Linux and not with PiGFX.

Tried several Pi Zeros (all non W) and all have the same symptoms.

Any ideas?

zaphodbe commented 4 years ago

Ok found the issue. Basically the issue is that for some calls to attach_timer_handler in the stupid_timer.c file. The hz parameter is 0 which results in an illegal divide in the following line and a very long time before the handler is called hence breaking the USB keyboard.

        timers[hnd].microsec_interval = 1000000 / hz;

So changed the code as follows to make sure the handler still get called in a timely fashion. The 0 might need to be more that that but either way this makes sure the handler gets called next time around the poll.

        if (hz) {
            timers[hnd].microsec_interval = 1000000 / hz;
        } else {
            timers[hnd].microsec_interval = 0;
        }
chregu82 commented 4 years ago

This is fixes with Version 1.1.5.