tq: rewrite for shift register semanticsHEADmaster

1 files changed, 59 insertions, 0 deletions

diff --git a/ThrottleQuadrant.cpp b/ThrottleQuadrant.cpp
new file mode 100644
index 0000000..4e4404a
--- /dev/null
+++ b/ThrottleQuadrant.cpp
@@ -0,0 +1,59 @@
+#include "ThrottleQuadrant.hpp"
+
+#include <limits.h>
+
+#include <Arduino.h>
+
+auto SaitekThrottleQuadrant::beginTransaction() -> void {
+  noInterrupts();
+  digitalWrite(latch_pin, LOW);
+  delayMicroseconds(latchDelayMicros);
+}
+
+auto SaitekThrottleQuadrant::endTransaction() -> void {
+  digitalWrite(latch_pin, HIGH);
+  delayMicroseconds(latchDelayMicros);
+  interrupts();
+}
+
+template<typename T, size_t Bits>
+auto SaitekThrottleQuadrant::doRead() -> T {
+  auto value = T{};
+
+  for (auto i = 0u; i < Bits; ++i) {
+    digitalWrite(clock_pin, LOW);
+    delayMicroseconds(clockDelayMicros);
+
+    value |= digitalRead(data_pin) << i;
+
+    digitalWrite(clock_pin, HIGH);
+    delayMicroseconds(clockDelayMicros);
+  }
+
+  return value;
+}
+
+auto SaitekThrottleQuadrant::begin(unsigned clock_pin, unsigned latch_pin, unsigned data_pin) -> void {
+  clock_pin = clock_pin;
+  latch_pin = latch_pin;
+  data_pin = data_pin;
+
+  pinMode(clock_pin, OUTPUT);
+  pinMode(latch_pin, OUTPUT);
+  pinMode(data_pin, INPUT);
+}
+
+auto SaitekThrottleQuadrant::read() noexcept -> Data {
+  auto result = Data{};
+
+  beginTransaction();
+
+  result.left = doRead<uint8_t>();
+  result.middle = doRead<uint8_t>();
+  result.right = doRead<uint8_t>();
+  result.buttons = doRead<uint16_t, numberOfButtons>();
+
+  endTransaction();
+
+  return result;
+}