altos: Change MAX6691 driver to run its own thread

This just captures temp data continuously; it takes 100ms to get the
temp data from the sensor, so the maximum rate is around 10 samples/sec.

Signed-off-by: Keith Packard <keithp@keithp.com>

diff --git a/src/drivers/ao_max6691.c b/src/drivers/ao_max6691.c
index c61d2c2197bad046070b05821efbd8da5ea37f47..5aeca506f46dc359bf9d4395bd8784b490e56450 100644 (file)
--- a/src/drivers/ao_max6691.c
+++ b/src/drivers/ao_max6691.c
@@ -43,8 +43,10 @@ ao_max6691_t_low(int channel)
        return ao_max6691_raw[channel * 2 + 4] - ao_max6691_raw[channel * 2 + 3];
 }
 
-void
-ao_max6691_sample(struct ao_max6691 *ao_max6691)
+struct ao_max6691_sample ao_max6691_current;
+
+static void
+ao_max6691_sample(void)
 {
        struct stm_tim234       *tim = AO_MAX6691_TIMER;
 
@@ -126,25 +128,32 @@ ao_max6691_sample(struct ao_max6691 *ao_max6691)
        ao_dma_done_transfer(AO_MAX6691_DMA);
 
        for (i = 0; i < AO_MAX6691_CHANNELS; i++) {
-               ao_max6691->sensor[i].t_high = ao_max6691_t_high(i);
-               ao_max6691->sensor[i].t_low = ao_max6691_t_low(i);
+               ao_max6691_current.sensor[i].t_high = ao_max6691_t_high(i);
+               ao_max6691_current.sensor[i].t_low = ao_max6691_t_low(i);
        }
 }
 
+static void
+ao_max6691(void)
+{
+       for (;;) {
+               ao_max6691_sample();
+               ao_arch_critical(AO_DATA_PRESENT(AO_DATA_MAX6691););
+       }
+}
+
+static struct ao_task ao_max6691_task;
+
 #define R_EXT  1000.0f
 
 static void
-ao_max6691_test(void)
+ao_max6691_dump(void)
 {
-       struct ao_max6691 ao_max6691;
+       struct ao_max6691_sample ao_max6691;
 
-       printf("Testing MAX6691\n"); flush();
-       ao_max6691_sample(&ao_max6691);
+       ao_max6691 = ao_max6691_current;
 
        int i;
-       for (i = 0; i < AO_MAX6691_SAMPLES; i++)
-               printf("%d: %5u\n", i, ao_max6691_raw[i]);
-
        for (i = 0; i < AO_MAX6691_CHANNELS; i++) {
                uint16_t        t_high = ao_max6691.sensor[i].t_high;
                uint16_t        t_low = ao_max6691.sensor[i].t_low;
@@ -179,12 +188,12 @@ ao_max6691_test(void)
 
                float Rth = R_EXT * (1 - V) / V;
 
-               printf("%d: high %5u low %5u ohms: %7g\n", i, t_high, t_low, Rth);
+               printf("max6691 channel %d: high %5u low %5u ohms: %7g\n", i, t_high, t_low, Rth);
        }
 }
 
 static const struct ao_cmds ao_max6691_cmds[] = {
-       { ao_max6691_test,      "q\0Thermistor test" },
+       { ao_max6691_dump,      "q\0Thermistor test" },
        { 0, NULL },
 };
 
@@ -243,4 +252,6 @@ ao_max6691_init(void)
 
        stm_ospeedr_set(AO_MAX6691_GPIO, AO_MAX6691_PIN, STM_OSPEEDR_40MHz);
        ao_enable_input(AO_MAX6691_GPIO, AO_MAX6691_PIN, AO_EXTI_MODE_PULL_UP);
+
+       ao_add_task(&ao_max6691_task, ao_max6691, "max6691");
 }

diff --git a/src/drivers/ao_max6691.h b/src/drivers/ao_max6691.h
index ab8207f9c7cabc0cd868aa3b3f3a0cc8adebc204..b6186daf74d7ef04664d93f0e0370869e2718b0f 100644 (file)
--- a/src/drivers/ao_max6691.h
+++ b/src/drivers/ao_max6691.h
@@ -17,15 +17,14 @@
 
 #define AO_MAX6691_CHANNELS    4
 
-struct ao_max6691 {
+struct ao_max6691_sample {
        struct {
                uint16_t        t_high;
                uint16_t        t_low;
        } sensor[AO_MAX6691_CHANNELS];
 };
 
-void
-ao_max6691_sample(struct ao_max6691 *ao_max6691);
+extern struct ao_max6691_sample ao_max6691_current;
 
 void
 ao_max6691_init(void);