altos: Pull igniter pins low as soon as possible at boot time

This reduces the pulse width on the igniter circuit caused by the
default cc1111 pin configuration at powerup time.

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

diff --git a/src/ao.h b/src/ao.h
index bb3c80ec2ddbb5e8580eb1f8fa9655a58914dec9..0699fc2ca70f52e73a22a88c687b3dceac05909e 100644 (file)
--- a/src/ao.h
+++ b/src/ao.h
@@ -1350,6 +1350,9 @@ enum ao_igniter_status {
 enum ao_igniter_status
 ao_igniter_status(enum ao_igniter igniter);
 
+void
+ao_ignite_set_pins(void);
+
 void
 ao_igniter_init(void);
 

diff --git a/src/ao_ignite.c b/src/ao_ignite.c
index 512ec6224ef2461f8b5c9799188ac7c645d3705e..5238beb4315663950e717f98629168b05bc4a419 100644 (file)
--- a/src/ao_ignite.c
+++ b/src/ao_ignite.c
@@ -202,11 +202,17 @@ __code struct ao_cmds ao_ignite_cmds[] = {
 __xdata struct ao_task ao_igniter_task;
 
 void
-ao_igniter_init(void)
+ao_ignite_set_pins(void)
 {
        AO_IGNITER_DROGUE = 0;
        AO_IGNITER_MAIN = 0;
        AO_IGNITER_DIR |= AO_IGNITER_DROGUE_BIT | AO_IGNITER_MAIN_BIT;
+}
+
+void
+ao_igniter_init(void)
+{
+       ao_ignite_set_pins();
        ao_cmd_register(&ao_ignite_cmds[0]);
        ao_add_task(&ao_igniter_task, ao_igniter, "igniter");
 }

diff --git a/src/ao_telemetrum.c b/src/ao_telemetrum.c
index 4ace415c23be7b3487f6bc9768c7a3b8b47e7bdd..d9ea1fc8c5c91e475b3d511aa71697ac64027a6e 100644 (file)
--- a/src/ao_telemetrum.c
+++ b/src/ao_telemetrum.c
@@ -28,8 +28,13 @@ ao_set_monitor(uint8_t monitoring)
 void
 main(void)
 {
-       ao_clock_init();
+       /*
+        * Reduce the transient on the ignite pins at startup by
+        * pulling the pins low as soon as possible at power up
+        */
+       ao_ignite_set_pins();
 
+       ao_clock_init();
 
        /* Turn on the red LED until the system is stable */
        ao_led_init(LEDS_AVAILABLE);