diff options
Diffstat (limited to 'core/units.h')
| -rw-r--r-- | core/units.h | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/core/units.h b/core/units.h index d44c50ab4..5e92a00ba 100644 --- a/core/units.h +++ b/core/units.h @@ -42,8 +42,11 @@ extern "C" { * We also strive to make '0' a meaningless number saying "not * initialized", since many values are things that may not have * been reported (eg cylinder pressure or temperature from dive - * computers that don't support them). But sometimes -1 is an even - * more explicit way of saying "not there". + * computers that don't support them). But for some of the values + * 0 doesn't works as a flag for not initialized. Examples are + * compass bearing (bearing_t) or NDL (duration_t). + * Therefore some types have a default value which is -1 and has to + * be set at certain points in the code. * * Thus "millibar" for pressure, for example, or "millikelvin" for * temperatures. Doing temperatures in celsius or fahrenheit would @@ -70,7 +73,7 @@ typedef int64_t timestamp_t; typedef struct { - uint32_t seconds; // durations up to 68 yrs + int32_t seconds; // durations up to 34 yrs } duration_t; typedef struct |