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authorGravatar Gediminas Jakutis <gediminas@varciai.lt> 2018-02-16 13:41:21 +0200
committerGravatar Gediminas Jakutis <gediminas@varciai.lt> 2018-02-16 13:41:21 +0200
commit4ab7c9eb681b133dcfeee1ecdd318780e6df170e (patch)
treeba1ab528529ec3a08d88e63b16a962732cec21c6 /src/tempmodule/temperature.c
parent00735224ca72ea64cfa4b882e2196c8fa03b9731 (diff)
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tempmodule: not even close to overflowing, swtich 64b -> 32b.
Diffstat (limited to 'src/tempmodule/temperature.c')
-rw-r--r--src/tempmodule/temperature.c3
1 files changed, 1 insertions, 2 deletions
diff --git a/src/tempmodule/temperature.c b/src/tempmodule/temperature.c
index 4f0a5f1..52fd7b7 100644
--- a/src/tempmodule/temperature.c
+++ b/src/tempmodule/temperature.c
@@ -16,7 +16,6 @@ struct temptuple {
*
* Rt = Ra * Vcc / Vt - Ra
*
- * Using 64-bit arithmetic as 32-bit would overflow.
* On WeMOS D1 Mini the A0 reads 3.2V as 1023; our Vcc is 3.31V
* The correct value of the reference volume obtained by measuring
* resistances with a multimeter, taking the ADC reading and applying
@@ -24,7 +23,7 @@ struct temptuple {
* We shift the range by one to avoid division by zero.
*/
-int get_resistance(int64_t vt, int64_t ra)
+int get_resistance(int vt, int ra)
{
++vt;
return ra * 1081 / vt - ra;