diff options
| author | syndycat <syndycat@yahoo.com> | 2017-01-07 13:36:11 +0200 |
|---|---|---|
| committer | Damien George <damien.p.george@gmail.com> | 2017-01-08 19:26:22 +1100 |
| commit | b2611d6be305c94359f67df875786858e05c3eb0 (patch) | |
| tree | e6555dd5867726a58db6f172308d9b3065598037 | |
| parent | 044f96c33010ae99cd5423358f4e41021423777b (diff) | |
| download | micropython-b2611d6be305c94359f67df875786858e05c3eb0.tar.gz micropython-b2611d6be305c94359f67df875786858e05c3eb0.zip | |
drivers/onewire/ds18x20: Fix negative temperature calc for DS18B20.
| -rw-r--r-- | drivers/onewire/ds18x20.py | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/onewire/ds18x20.py b/drivers/onewire/ds18x20.py index a2f7f5c3da..342f4b28ae 100644 --- a/drivers/onewire/ds18x20.py +++ b/drivers/onewire/ds18x20.py @@ -93,6 +93,9 @@ class DS18X20(object): temp = temp_read - 0.25 + (count_per_c - count_remain) / count_per_c return temp elif rom0 == 0x28: - return (temp_msb << 8 | temp_lsb) / 16 + temp = (temp_msb << 8 | temp_lsb) / 16 + if (temp_msb & 0xf8) == 0xf8: # for negative temperature + temp -= 0x1000 + return temp else: assert False |