1 files changed, 4 insertions(+), 0 deletions(-)

M src/pin.c

@@ 67,6 67,10 @@ void pin_into_input_highspeed(pin_t *pin) {
 
 void pin_into_alternate(pin_t *pin, uint8_t alternate) {
   pin_mode(pin, ALTERNATE);
+  uint8_t index = pin->pin >> 3;
+  uint8_t pos = (pin->pin & 0x7) * 4;
+  volatile uint32_t *afr = pin->gpio->AFR;
+  reg_set_bits_pos(afr + index, alternate, pos, 0xF);
 }
 void pin_into_alternate_highspeed(pin_t *pin, uint8_t alternate) {
   pin_into_alternate(pin, alternate);