djsundog/circuitpython
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

extmod/modonewire: Use pin_od_high/pin_od_low instead of pin_write.

Browse Source 
The pin is configured in open-drain mode so these od_high/od_low methods
should be used.

Signed-off-by: Damien George <damien@micropython.org>
This commit is contained in:
Damien George 2021-01-21 01:19:46 +11:00
parent 794df0f1d5
commit ec0503bd0c
1 changed files with 8 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
extmod/modonewire.c
View File

@ -44,10 +44,10 @@
#define TIMING_WRITE3 (10)
STATIC int onewire_bus_reset(mp_hal_pin_obj_t pin) {
mp_hal_pin_write(pin, 0);
mp_hal_pin_od_low(pin);
mp_hal_delay_us(TIMING_RESET1);
uint32_t i = mp_hal_quiet_timing_enter();
mp_hal_pin_write(pin, 1);
mp_hal_pin_od_high(pin);
mp_hal_delay_us_fast(TIMING_RESET2);
int status = !mp_hal_pin_read(pin);
mp_hal_quiet_timing_exit(i);
@ -56,11 +56,11 @@ STATIC int onewire_bus_reset(mp_hal_pin_obj_t pin) {
}
STATIC int onewire_bus_readbit(mp_hal_pin_obj_t pin) {
mp_hal_pin_write(pin, 1);
mp_hal_pin_od_high(pin);
uint32_t i = mp_hal_quiet_timing_enter();
mp_hal_pin_write(pin, 0);
mp_hal_pin_od_low(pin);
mp_hal_delay_us_fast(TIMING_READ1);
mp_hal_pin_write(pin, 1);
mp_hal_pin_od_high(pin);
mp_hal_delay_us_fast(TIMING_READ2);
int value = mp_hal_pin_read(pin);
mp_hal_quiet_timing_exit(i);
@ -70,13 +70,13 @@ STATIC int onewire_bus_readbit(mp_hal_pin_obj_t pin) {
STATIC void onewire_bus_writebit(mp_hal_pin_obj_t pin, int value) {
uint32_t i = mp_hal_quiet_timing_enter();
mp_hal_pin_write(pin, 0);
mp_hal_pin_od_low(pin);
mp_hal_delay_us_fast(TIMING_WRITE1);
if (value) {
mp_hal_pin_write(pin, 1);
mp_hal_pin_od_high(pin);
}
mp_hal_delay_us_fast(TIMING_WRITE2);
mp_hal_pin_write(pin, 1);
mp_hal_pin_od_high(pin);
mp_hal_delay_us_fast(TIMING_WRITE3);
mp_hal_quiet_timing_exit(i);
}