dmm: vc870: fix AC conversion factors

Testing showed that AC current needs to be handled different from DC.
Note that ACA is still untested because of limited testing equipment.

Signed-off-by: Wolfram Sang <redacted>

diff --git a/src/dmm/vc870.c b/src/dmm/vc870.c
index d14b84152c63240f9ab29ddf7f91b43db458889c..ee61483b6aec61114477066c89dd990ded6d8955 100644 (file)
--- a/src/dmm/vc870.c
+++ b/src/dmm/vc870.c
@@ -46,11 +46,17 @@ static const float factors[][8] = {
        {1e-4,  0,     0,     0,    0,    0,    0,    0},    /* Diode */
        {1e-3,  1e-2,  1e-1,  1,    1e1,  1e2,  1e3,  1e4},  /* Frequency */
        {1e-2,  0,     0,     0,    0,    0,    0,    0},    /* Loop current */
+       /*
+        * Note: Measurements showed that AC and DC differ
+        * in the factors used, although docs say they should
+        * be the same.
+        */
        {1e-8,  1e-7,  0,     0,    0,    0,    0,    0},    /* DCµA */
-       {1e-8,  1e-7,  0,     0,    0,    0,    0,    0},    /* ACµA */
+       {1e-7,  1e-6,  0,     0,    0,    0,    0,    0},    /* ACµA */
        {1e-6,  1e-5,  0,     0,    0,    0,    0,    0},    /* DCmA */
-       {1e-6,  1e-5,  0,     0,    0,    0,    0,    0},    /* ACmA */
+       {1e-5,  1e-4,  0,     0,    0,    0,    0,    0},    /* ACmA */
        {1e-3,  0,     0,     0,    0,    0,    0,    0},    /* DCA */
+       /* TODO: Verify factor for ACA */
        {1e-3,  0,     0,     0,    0,    0,    0,    0},    /* ACA */
        {1e-1,  0,     0,     0,    0,    0,    0,    0},    /* Act+apparent power */
        {1e-1,  0,     0,     0,    0,    0,    0,    0},    /* Power factor / freq */