diff options
Diffstat (limited to 'hid/pico/src/ph_ps2_phy.pio')
| -rw-r--r-- | hid/pico/src/ph_ps2_phy.pio | 23 |
1 files changed, 11 insertions, 12 deletions
diff --git a/hid/pico/src/ph_ps2_phy.pio b/hid/pico/src/ph_ps2_phy.pio index 055cc6d7..a2e4c81f 100644 --- a/hid/pico/src/ph_ps2_phy.pio +++ b/hid/pico/src/ph_ps2_phy.pio @@ -9,8 +9,8 @@ .side_set 1 opt pindirs restart: - irq clear 0 rel - set pindirs 0 side 0 // clock and data to input mode + set pindirs 0 [4] // set clock to input mode + irq clear 0 rel side 0 // clear busy flag, set data to input mode receivecheck: jmp pin sendcheck // if clock is high, see if we have data to send @@ -20,17 +20,17 @@ receivecheck: // we are not sending, look for a start bit (clock high, data low) in pins 1 // read in from data mov x isr // move what we read to x - mov isr null // clear ISR. - jmp !x receive // if x is low, start the receive process. + mov isr null // clear ISR + jmp !x receive // if x is low, start the receive process jmp restart // not receiving receive: - set pindirs, 1 [6] // clock low. - set x, 8 // set loop counter. + set pindirs, 1 [6] // clock low + set x, 8 // set loop counter receiveloop: set pindirs, 0 [6] // clock high - in pins, 1 [4] // read a bit into ISR. + in pins, 1 [4] // read a bit into ISR set pindirs, 1 [6] // clock low jmp x-- receiveloop [4] // iterate set pindirs, 0 [6] // clock high @@ -43,15 +43,14 @@ sendcheck: jmp receivecheck // no data to send, restart wait_to_write: - irq set 0 rel - set x 10 // number of bits to write out + irq set 0 rel // set busy flag + set x 10 // number of bits to write out sendloop: set pindirs, 0 [6] // clock set to input (high) jmp pin sendcontinue // if clock is high, host is still receiving data - irq set 1 rel // clock was low, host wants to send data, notify of failure to send data - mov osr null // clear OSR - jmp restart + irq wait 1 rel // clock was low, host wants to send data, notify of failure to send data + jmp restart // and wait for restart sendcontinue: out pindirs, 1 [6] // write out data set pindirs, 1 [6] // set clock low |