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

atmel-samd: Tweak DAC logic for clarity. Thanks @bcr for the suggestion.

Browse Source
This commit is contained in:
Scott Shawcroft 2016-10-21 17:08:14 -07:00
parent 30dc24191f
commit f5ca66805b
1 changed files with 1 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
atmel-samd/modmachine_dac.c
View File

@ -118,10 +118,7 @@ STATIC mp_obj_t dac_write_mv(mp_obj_t self_in, mp_obj_t val_mv) {
dac_obj_t *self = self_in;
// TODO(tannewt): Sanity check that the mv value is less than the reference
// voltage.
// Dividing by 3301 instead of 3300 ensures that val_mv of 3300 actually
// produces a value of 1023 instead of 1024 which is out of range of the
// DAC.
uint16_t val = ((uint32_t) mp_obj_get_int(val_mv)) * 1024 / 3301;
uint16_t val = ((uint32_t) mp_obj_get_int(val_mv)) * 1023 / 3300;
dac_chan_write(&self->dac_instance, DAC_CHANNEL_0, val);