initial entry of SPI driver - no testing/build performed

Author: gigapod

src/sfTk/sfDevFPC2534SPI.cpp

@@ -0,0 +1,122 @@
+/*
+ *---------------------------------------------------------------------------------
+ *
+ * Copyright (c) 2025, SparkFun Electronics Inc.
+ *
+ * SPDX-License-Identifier: MIT
+ *
+ *---------------------------------------------------------------------------------
+ */
+
+#include "sfDevFPC2534SPI.h"
+
+// --------------------------------------------------------------------------------------------
+// CTOR
+sfDevFPC2534SPI::sfDevFPC2534SPI() : _spiPort{nullptr}, _spiSettings{nullptr}, _csPin{0}
+{
+}
+
+//--------------------------------------------------------------------------------------------
+bool sfDevFPC2534SPI::initialize(SPIClass &spiPort, SPISettings &busSPISettings, uint8_t csPin, uint32_t interruptPin,
+                                 bool bInit)
+
+{
+    _spiPort = &spiPort;
+
+    _spiSettings = busSPISettings;
+    _csPin = csPin;
+
+    // Call our super to init the ISR handler
+    sfDevFPC2534IComm::initISRHandler(interruptPin);
+
+    // clear out our data buffer
+    clearData();
+
+    return true;
+}
+//--------------------------------------------------------------------------------------------
+bool sfDevFPC2534SPI::initialize(uint8_t csPin, uint32_t interruptPin, bool bInit)
+{
+    return initialize(SPI, SPISettings(3000000, MSBFIRST, SPI_MODE3), csPin, interruptPin, bInit);
+}
+//--------------------------------------------------------------------------------------------
+// Is data available to read - either the device is indicating it via an interrupt, or we have
+// data in our internal buffer
+//
+bool sfDevFPC2534SPI::dataAvailable()
+{
+    if (_spiPort == nullptr)
+        return false;
+
+    // the data available flag is set, or we have data in the buffer
+    return isISRDataAvailable() || _dataCount > 0;
+}
+
+//--------------------------------------------------------------------------------------------
+// Clear out the internal data buffer...
+//
+void sfDevFPC2534SPI::clearData()
+{
+    // clear any data signaled by the ISR
+    clearISRDataAvailable();
+}
+
+//--------------------------------------------------------------------------------------------
+// Write data to the device
+//
+uint16_t sfDevFPC2534SPI::write(const uint8_t *data, size_t len)
+{
+    if (_spiPort == nullptr)
+        return FPC_RESULT_IO_RUNTIME_FAILURE; // I2C bus not initialized
+
+    _spiPort->beginTransaction(_spiSettings);
+
+    // Signal communication start
+    digitalWrite(_csPin, LOW);
+
+    // the  datasheet specifiies a delay greater than 500us after CS goes low
+    delayMicroseconds(600);
+
+    // now send the data
+    for (size_t i = 0; i < len; i++)
+        _spiPort->transfer(*data++);
+
+    // End comms
+    digitalWrite(_csPin, HIGH);
+    _spiPort->endTransaction();
+
+    return FPC_RESULT_OK;
+}
+
+//--------------------------------------------------------------------------------------------
+uint16_t sfDevFPC2534SPI::read(uint8_t *data, size_t len)
+{
+    // got port
+    if (_spiPort == nullptr)
+        return FPC_RESULT_IO_RUNTIME_FAILURE;
+
+    if (len == 0)
+        return FPC_RESULT_OK;
+
+    // lets return data to the user...
+    if (data == nullptr)
+        return FPC_RESULT_INVALID_PARAM;
+
+    _spiPort->beginTransaction(_spiSettings);
+
+    // Signal communication start
+    digitalWrite(_csPin, LOW);
+
+    // the  datasheet specifiies a delay greater than 500us after CS goes low
+    delayMicroseconds(600);
+
+    // Lets read the data...
+    for (size_t i = 0; i < len; i++)
+        *data++ = _spiPort->transfer(0x00);
+
+    // End transaction
+    digitalWrite(_csPin, HIGH);
+    _spiPort->endTransaction();
+
+    return FPC_RESULT_OK;
+}

src/sfTk/sfDevFPC2534SPI.h

@@ -0,0 +1,39 @@
+/*
+ *---------------------------------------------------------------------------------
+ *
+ * Copyright (c) 2025, SparkFun Electronics Inc.
+ *
+ * SPDX-License-Identifier: MIT
+ *
+ *---------------------------------------------------------------------------------
+ */
+
+#pragma once
+
+// from the FPC SDK
+#include "fpc_api.h"
+
+#include <Arduino.h>
+#include <SPI.h>
+
+// SPI impl for the FPC2534 communication interface
+
+class sfDevFPC2534SPI : public sfDevFPC2534IComm
+{
+  public:
+    sfDevFPC2534SPI();
+    bool initialize(SPIClass &spiPort, SPISettings &busSPISettings, uint8_t csPin, uint32_t interruptPin,
+                    bool bInit = false);
+    bool initialize(uint8_t csPin, uint32_t interruptPin, bool bInit = false);
+
+    bool dataAvailable();
+    void clearData();
+    uint16_t write(const uint8_t *data, size_t len);
+    uint16_t read(uint8_t *data, size_t len);
+
+  private:
+    // SPI Things
+    SPIClass *_spiPort;
+    SPISettings _spiSettings;
+    uint8_t _csPin;
+};