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authorBdale Garbee <bdale@gag.com>2012-08-28 23:39:53 -0600
committerBdale Garbee <bdale@gag.com>2012-08-28 23:39:53 -0600
commit5ed88fb72c3e3ecf3333c700d838667db71cfbdc (patch)
tree3b371f563c0f7607f2fe53242673adb352b48514 /src/drivers/ao_quadrature.c
parentadbe64c5a9402b7c5075a444a12629131b663877 (diff)
parent621d0930244f25165d2ac5da596dcc87e253b965 (diff)
Merge branch 'master' of ssh://git.gag.com/scm/git/fw/altos
Conflicts: debian/control
Diffstat (limited to 'src/drivers/ao_quadrature.c')
-rw-r--r--src/drivers/ao_quadrature.c134
1 files changed, 134 insertions, 0 deletions
diff --git a/src/drivers/ao_quadrature.c b/src/drivers/ao_quadrature.c
new file mode 100644
index 00000000..6cc2467a
--- /dev/null
+++ b/src/drivers/ao_quadrature.c
@@ -0,0 +1,134 @@
+/*
+ * Copyright © 2012 Keith Packard <keithp@keithp.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ */
+
+#include <ao.h>
+#include <ao_quadrature.h>
+#include <ao_exti.h>
+#if AO_EVENT
+#include <ao_event.h>
+#define ao_quadrature_queue(q) ao_event_put_isr(AO_EVENT_QUADRATURE, q, ao_quadrature_count[q])
+#else
+#define ao_quadrature_queue(q)
+#endif
+
+__xdata int32_t ao_quadrature_count[AO_QUADRATURE_COUNT];
+
+static uint8_t ao_quadrature_state[AO_QUADRATURE_COUNT];
+
+#define BIT(a,b) ((a) | ((b) << 1))
+#define STATE(old_a, old_b, new_a, new_b) (((BIT(old_a, old_b) << 2) | BIT(new_a, new_b)))
+
+#define port(q) AO_QUADRATURE_ ## q ## _PORT
+#define bita(q) AO_QUADRATURE_ ## q ## _A
+#define bitb(q) AO_QUADRATURE_ ## q ## _B
+
+#define ao_quadrature_update(q) do { \
+ ao_quadrature_state[q] = ((ao_quadrature_state[q] & 3) << 2); \
+ ao_quadrature_state[q] |= ao_gpio_get(port(q), bita(q), 0); \
+ ao_quadrature_state[q] |= ao_gpio_get(port(q), bitb(q), 0) << 1; \
+ } while (0)
+
+
+static void
+ao_quadrature_isr(void)
+{
+ uint8_t q;
+#if AO_QUADRATURE_COUNT > 0
+ ao_quadrature_update(0);
+#endif
+#if AO_QUADRATURE_COUNT > 1
+ ao_quadrature_update(1);
+#endif
+
+ for (q = 0; q < AO_QUADRATURE_COUNT; q++) {
+ switch (ao_quadrature_state[q]) {
+ case STATE(0, 1, 0, 0):
+ ao_quadrature_count[q]++;
+ break;
+ case STATE(1, 0, 0, 0):
+ ao_quadrature_count[q]--;
+ break;
+ default:
+ continue;
+ }
+ ao_quadrature_queue(q);
+ ao_wakeup(&ao_quadrature_count[q]);
+ }
+}
+
+int32_t
+ao_quadrature_poll(uint8_t q)
+{
+ int32_t ret;
+ ao_arch_critical(ret = ao_quadrature_count[q];);
+ return ret;
+}
+
+int32_t
+ao_quadrature_wait(uint8_t q)
+{
+ ao_sleep(&ao_quadrature_count[q]);
+ return ao_quadrature_poll(q);
+}
+
+static void
+ao_quadrature_test(void)
+{
+ uint8_t q;
+
+ ao_cmd_decimal();
+ q = ao_cmd_lex_i;
+ for (;;) {
+ int32_t c;
+ flush();
+ c = ao_quadrature_wait(q);
+ printf ("new count %6d\n", c);
+ if (c == 100)
+ break;
+ }
+}
+
+static const struct ao_cmds ao_quadrature_cmds[] = {
+ { ao_quadrature_test, "q <unit>\0Test quadrature" },
+ { 0, NULL }
+};
+
+#define init(q) do { \
+ ao_enable_port(port(q)); \
+ \
+ ao_exti_setup(port(q), bita(q), \
+ AO_QUADRATURE_MODE|AO_EXTI_MODE_FALLING|AO_EXTI_MODE_RISING|AO_EXTI_PRIORITY_MED, \
+ ao_quadrature_isr); \
+ ao_exti_enable(port(q), bita(q)); \
+ \
+ ao_exti_setup(port(q), bitb(q), \
+ AO_QUADRATURE_MODE|AO_EXTI_MODE_FALLING|AO_EXTI_MODE_RISING|AO_EXTI_PRIORITY_MED, \
+ ao_quadrature_isr); \
+ ao_exti_enable(port(q), bitb(q)); \
+ } while (0)
+
+void
+ao_quadrature_init(void)
+{
+#if AO_QUADRATURE_COUNT > 0
+ init(0);
+#endif
+#if AO_QUADRATURE_COUNT > 1
+ init(1);
+#endif
+ ao_cmd_register(&ao_quadrature_cmds[0]);
+}