Added ahal
This is a formatted copy of WPILib's default user-visible C++ API, with
a bit of completely unnecessary functionality stripped out. Most of the
stripping so far is only related to weird threading decisions.
Change-Id: Icbfd949b48cd115561862cb909bcc572aba0e753
diff --git a/frc971/wpilib/ahal/Relay.cc b/frc971/wpilib/ahal/Relay.cc
new file mode 100644
index 0000000..b69e7af
--- /dev/null
+++ b/frc971/wpilib/ahal/Relay.cc
@@ -0,0 +1,204 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) FIRST 2008-2017. All Rights Reserved. */
+/* Open Source Software - may be modified and shared by FRC teams. The code */
+/* must be accompanied by the FIRST BSD license file in the root directory of */
+/* the project. */
+/*----------------------------------------------------------------------------*/
+
+#include "HAL/Relay.h"
+#include "frc971/wpilib/ahal/Relay.h"
+
+#include <sstream>
+
+#include "HAL/HAL.h"
+#include "HAL/Ports.h"
+#include "frc971/wpilib/ahal/WPIErrors.h"
+
+using namespace frc;
+
+/**
+ * Relay constructor given a channel.
+ *
+ * This code initializes the relay and reserves all resources that need to be
+ * locked. Initially the relay is set to both lines at 0v.
+ *
+ * @param channel The channel number (0-3).
+ * @param direction The direction that the Relay object will control.
+ */
+Relay::Relay(int channel, Relay::Direction direction)
+ : m_channel(channel), m_direction(direction) {
+ std::stringstream buf;
+ if (!CheckRelayChannel(m_channel)) {
+ buf << "Relay Channel " << m_channel;
+ wpi_setWPIErrorWithContext(ChannelIndexOutOfRange, buf.str());
+ return;
+ }
+
+ HAL_PortHandle portHandle = HAL_GetPort(channel);
+
+ if (m_direction == kBothDirections || m_direction == kForwardOnly) {
+ int32_t status = 0;
+ m_forwardHandle = HAL_InitializeRelayPort(portHandle, true, &status);
+ if (status != 0) {
+ wpi_setErrorWithContextRange(status, 0, HAL_GetNumRelayChannels(),
+ channel, HAL_GetErrorMessage(status));
+ m_forwardHandle = HAL_kInvalidHandle;
+ m_reverseHandle = HAL_kInvalidHandle;
+ return;
+ }
+ HAL_Report(HALUsageReporting::kResourceType_Relay, m_channel);
+ }
+ if (m_direction == kBothDirections || m_direction == kReverseOnly) {
+ int32_t status = 0;
+ m_reverseHandle = HAL_InitializeRelayPort(portHandle, false, &status);
+ if (status != 0) {
+ wpi_setErrorWithContextRange(status, 0, HAL_GetNumRelayChannels(),
+ channel, HAL_GetErrorMessage(status));
+ m_forwardHandle = HAL_kInvalidHandle;
+ m_reverseHandle = HAL_kInvalidHandle;
+ return;
+ }
+
+ HAL_Report(HALUsageReporting::kResourceType_Relay, m_channel + 128);
+ }
+
+ int32_t status = 0;
+ if (m_forwardHandle != HAL_kInvalidHandle) {
+ HAL_SetRelay(m_forwardHandle, false, &status);
+ if (status != 0) {
+ wpi_setErrorWithContext(status, HAL_GetErrorMessage(status));
+ m_forwardHandle = HAL_kInvalidHandle;
+ m_reverseHandle = HAL_kInvalidHandle;
+ return;
+ }
+ }
+ if (m_reverseHandle != HAL_kInvalidHandle) {
+ HAL_SetRelay(m_reverseHandle, false, &status);
+ if (status != 0) {
+ wpi_setErrorWithContext(status, HAL_GetErrorMessage(status));
+ m_forwardHandle = HAL_kInvalidHandle;
+ m_reverseHandle = HAL_kInvalidHandle;
+ return;
+ }
+ }
+}
+
+/**
+ * Free the resource associated with a relay.
+ *
+ * The relay channels are set to free and the relay output is turned off.
+ */
+Relay::~Relay() {
+ int32_t status = 0;
+ HAL_SetRelay(m_forwardHandle, false, &status);
+ HAL_SetRelay(m_reverseHandle, false, &status);
+ // ignore errors, as we want to make sure a free happens.
+ if (m_forwardHandle != HAL_kInvalidHandle) HAL_FreeRelayPort(m_forwardHandle);
+ if (m_reverseHandle != HAL_kInvalidHandle) HAL_FreeRelayPort(m_reverseHandle);
+}
+
+/**
+ * Set the relay state.
+ *
+ * Valid values depend on which directions of the relay are controlled by the
+ * object.
+ *
+ * When set to kBothDirections, the relay can be any of the four states:
+ * 0v-0v, 0v-12v, 12v-0v, 12v-12v
+ *
+ * When set to kForwardOnly or kReverseOnly, you can specify the constant for
+ * the direction or you can simply specify kOff and kOn. Using only kOff and
+ * kOn is recommended.
+ *
+ * @param value The state to set the relay.
+ */
+void Relay::Set(Relay::Value value) {
+ if (StatusIsFatal()) return;
+
+ int32_t status = 0;
+
+ switch (value) {
+ case kOff:
+ if (m_direction == kBothDirections || m_direction == kForwardOnly) {
+ HAL_SetRelay(m_forwardHandle, false, &status);
+ }
+ if (m_direction == kBothDirections || m_direction == kReverseOnly) {
+ HAL_SetRelay(m_reverseHandle, false, &status);
+ }
+ break;
+ case kOn:
+ if (m_direction == kBothDirections || m_direction == kForwardOnly) {
+ HAL_SetRelay(m_forwardHandle, true, &status);
+ }
+ if (m_direction == kBothDirections || m_direction == kReverseOnly) {
+ HAL_SetRelay(m_reverseHandle, true, &status);
+ }
+ break;
+ case kForward:
+ if (m_direction == kReverseOnly) {
+ wpi_setWPIError(IncompatibleMode);
+ break;
+ }
+ if (m_direction == kBothDirections || m_direction == kForwardOnly) {
+ HAL_SetRelay(m_forwardHandle, true, &status);
+ }
+ if (m_direction == kBothDirections) {
+ HAL_SetRelay(m_reverseHandle, false, &status);
+ }
+ break;
+ case kReverse:
+ if (m_direction == kForwardOnly) {
+ wpi_setWPIError(IncompatibleMode);
+ break;
+ }
+ if (m_direction == kBothDirections) {
+ HAL_SetRelay(m_forwardHandle, false, &status);
+ }
+ if (m_direction == kBothDirections || m_direction == kReverseOnly) {
+ HAL_SetRelay(m_reverseHandle, true, &status);
+ }
+ break;
+ }
+
+ wpi_setErrorWithContext(status, HAL_GetErrorMessage(status));
+}
+
+/**
+ * Get the Relay State
+ *
+ * Gets the current state of the relay.
+ *
+ * When set to kForwardOnly or kReverseOnly, value is returned as kOn/kOff not
+ * kForward/kReverse (per the recommendation in Set)
+ *
+ * @return The current state of the relay as a Relay::Value
+ */
+Relay::Value Relay::Get() const {
+ int32_t status;
+
+ if (HAL_GetRelay(m_forwardHandle, &status)) {
+ if (HAL_GetRelay(m_reverseHandle, &status)) {
+ return kOn;
+ } else {
+ if (m_direction == kForwardOnly) {
+ return kOn;
+ } else {
+ return kForward;
+ }
+ }
+ } else {
+ if (HAL_GetRelay(m_reverseHandle, &status)) {
+ if (m_direction == kReverseOnly) {
+ return kOn;
+ } else {
+ return kReverse;
+ }
+ } else {
+ return kOff;
+ }
+ }
+
+ wpi_setErrorWithContext(status, HAL_GetErrorMessage(status));
+}
+
+int Relay::GetChannel() const { return m_channel; }