spi register support

Adafruit_BusIO_Register.cpp

@@ -1,6 +1,7 @@
 #include <Adafruit_BusIO_Register.h>
 
-Adafruit_BusIO_Register::Adafruit_BusIO_Register(Adafruit_I2CDevice *i2cdevice, uint16_t reg_addr, uint8_t width, uint8_t bitorder, uint8_t address_width) {
+Adafruit_BusIO_Register::Adafruit_BusIO_Register(Adafruit_I2CDevice *i2cdevice, uint16_t reg_addr, 
+						 uint8_t width, uint8_t bitorder, uint8_t address_width) {
   _i2cdevice = i2cdevice;
   _spidevice = NULL;
   _addrwidth = address_width;
@@ -9,23 +10,32 @@ Adafruit_BusIO_Register::Adafruit_BusIO_Register(Adafruit_I2CDevice *i2cdevice,
   _width = width;
 }
 
-/*
-Adafruit_BusIO_Register::Adafruit_BusIO_Register(Adafruit_SPIDevice *spidevice, uint16_t reg_addr, uint8_t width, uint8_t bitorder, uint8_t address_width) {
+Adafruit_BusIO_Register::Adafruit_BusIO_Register(Adafruit_SPIDevice *spidevice, uint16_t reg_addr, 
+						 Adafruit_BusIO_SPIRegType type,
+						 uint8_t width, uint8_t bitorder, uint8_t address_width) {
   _spidevice = spidevice;
+  _spiregtype = type;
   _i2cdevice = NULL;
   _addrwidth = address_width;
   _address = reg_addr;
   _bitorder = bitorder;
   _width = width;
 }
-*/
 
 bool Adafruit_BusIO_Register::write(uint8_t *buffer, uint8_t len) {
+
   uint8_t addrbuffer[2] = {(uint8_t)(_address & 0xFF), (uint8_t)(_address>>8)};
-  if (_i2cdevice && ! _i2cdevice->write(buffer, len, true, addrbuffer, _addrwidth)) {
-    return false;
+
+  if (_i2cdevice) {
+    return _i2cdevice->write(buffer, len, true, addrbuffer, _addrwidth);
   }
-  return true;
+  if (_spidevice) {
+    if (_spiregtype == ADDRBIT8_HIGH_TOREAD) {
+      addrbuffer[0] &= ~0x80;
+    }
+    return _spidevice->write( buffer, len, addrbuffer, _addrwidth);
+  }
+  return false;
 }
 
 bool Adafruit_BusIO_Register::write(uint32_t value, uint8_t numbytes) {
@@ -69,11 +79,18 @@ uint32_t Adafruit_BusIO_Register::read(void) {
 
 
 bool Adafruit_BusIO_Register::read(uint8_t *buffer, uint8_t len) {
-  _buffer[0] = _address;
-  if (_i2cdevice && ! _i2cdevice->write_then_read(_buffer, 1, buffer, len)) {
-    return false;
+  uint8_t addrbuffer[2] = {(uint8_t)(_address & 0xFF), (uint8_t)(_address>>8)};
+
+  if (_i2cdevice) {
+    return _i2cdevice->write_then_read(addrbuffer, _addrwidth, buffer, len);
   }
-  return true;
+  if (_spidevice) {
+    if (_spiregtype == ADDRBIT8_HIGH_TOREAD) {
+      addrbuffer[0] |= 0x80;
+    }
+    return _spidevice->write_then_read(addrbuffer, _addrwidth, buffer, len);
+  }
+  return false;
 }
 
 bool Adafruit_BusIO_Register::read(uint16_t *value) {

Adafruit_BusIO_Register.h

@@ -6,13 +6,19 @@
 #ifndef Adafruit_BusIO_Register_h
 #define Adafruit_BusIO_Register_h
 
+typedef enum _Adafruit_BusIO_SPIRegType {
+  ADDRBIT8_HIGH_TOREAD = 0,
+} Adafruit_BusIO_SPIRegType;
 
 class Adafruit_BusIO_Register {
  public:
   Adafruit_BusIO_Register(Adafruit_I2CDevice *i2cdevice, uint16_t reg_addr, 
-		       uint8_t width=1, uint8_t bitorder=LSBFIRST,
-		       uint8_t address_width=1); 
-
+			  uint8_t width=1, uint8_t bitorder=LSBFIRST,
+			  uint8_t address_width=1); 
+  Adafruit_BusIO_Register(Adafruit_SPIDevice *spidevice, uint16_t reg_addr, 
+			  Adafruit_BusIO_SPIRegType type,
+			  uint8_t width=1, uint8_t bitorder=LSBFIRST,
+			  uint8_t address_width=1); 
   bool read(uint8_t *buffer, uint8_t len);
   bool read(uint8_t *value);
   bool read(uint16_t *value);
@@ -29,6 +35,7 @@ class Adafruit_BusIO_Register {
  private:
   Adafruit_I2CDevice *_i2cdevice;
   Adafruit_SPIDevice *_spidevice;
+  Adafruit_BusIO_SPIRegType _spiregtype;
   uint16_t _address;
   uint8_t _width, _addrwidth, _bitorder;
   uint8_t _buffer[4];      // we wont support anything larger than uint32 for non-buffered read

Adafruit_SPIDevice.cpp

@@ -1,7 +1,7 @@
 #include <Adafruit_SPIDevice.h>
 #include <Arduino.h>
 
-//#define DEBUG_SERIAL Serial
+#define DEBUG_SERIAL Serial
 
 Adafruit_SPIDevice::Adafruit_SPIDevice(int8_t cspin, uint32_t freq, BitOrder dataOrder, uint8_t dataMode, SPIClass *theSPI) {
   _cs = cspin;
@@ -19,8 +19,38 @@ bool Adafruit_SPIDevice::begin(void) {
 }
 
 bool Adafruit_SPIDevice::write(uint8_t *buffer, size_t len, uint8_t *prefix_buffer, size_t prefix_len) {
+  _spi->beginTransaction(*_spiSetting);
+  digitalWrite(_cs, LOW);
+  // do the writing
+  for (int i=0; i<prefix_len; i++) {
+    _spi->transfer(prefix_buffer[i]);
+  }
+  for (int i=0; i<len; i++) {
+    _spi->transfer(buffer[i]);
+  }
+  digitalWrite(_cs, HIGH);
+  _spi->endTransaction();
 
 
+#ifdef DEBUG_SERIAL
+  DEBUG_SERIAL.print(F("\tSPIDevice Wrote: "));
+  if ((prefix_len != 0) && (prefix_buffer != NULL)) {
+    for (uint16_t i=0; i<prefix_len; i++) {
+      DEBUG_SERIAL.print(F("0x")); 
+      DEBUG_SERIAL.print(prefix_buffer[i], HEX); 
+      DEBUG_SERIAL.print(F(", "));
+    }
+  }
+  for (uint16_t i=0; i<len; i++) {
+    DEBUG_SERIAL.print(F("0x")); 
+    DEBUG_SERIAL.print(buffer[i], HEX); 
+    DEBUG_SERIAL.print(F(", "));
+    if (len % 32 == 31) {
+      DEBUG_SERIAL.println();
+    }
+  }
+  DEBUG_SERIAL.println();
+#endif
 
   return true;
 }
@@ -33,6 +63,19 @@ bool Adafruit_SPIDevice::read(uint8_t *buffer, size_t len, uint8_t sendvalue) {
   digitalWrite(_cs, HIGH);
   _spi->endTransaction();
 
+#ifdef DEBUG_SERIAL
+  DEBUG_SERIAL.print(F("\tSPIDevice Read: "));
+  for (uint16_t i=0; i<len; i++) {
+    DEBUG_SERIAL.print(F("0x")); 
+    DEBUG_SERIAL.print(buffer[i], HEX); 
+    DEBUG_SERIAL.print(F(", "));
+    if (len % 32 == 31) {
+      DEBUG_SERIAL.println();
+    }
+  }
+  DEBUG_SERIAL.println();
+#endif
+
   return true;
 }
 
@@ -45,10 +88,38 @@ bool Adafruit_SPIDevice::write_then_read(uint8_t *write_buffer, size_t write_len
   for (int i=0; i<write_len; i++) {
     _spi->transfer(write_buffer[i]);
   }
+
+#ifdef DEBUG_SERIAL
+  DEBUG_SERIAL.print(F("\tSPIDevice Wrote: "));
+  for (uint16_t i=0; i<write_len; i++) {
+    DEBUG_SERIAL.print(F("0x")); 
+    DEBUG_SERIAL.print(write_buffer[i], HEX); 
+    DEBUG_SERIAL.print(F(", "));
+    if (write_len % 32 == 31) {
+      DEBUG_SERIAL.println();
+    }
+  }
+  DEBUG_SERIAL.println();
+#endif
+
   // do the reading
   for (int i=0; i<read_len; i++) {
     read_buffer[i] = _spi->transfer(sendvalue);
   }
+
+#ifdef DEBUG_SERIAL
+  DEBUG_SERIAL.print(F("\tSPIDevice Read: "));
+  for (uint16_t i=0; i<read_len; i++) {
+    DEBUG_SERIAL.print(F("0x")); 
+    DEBUG_SERIAL.print(read_buffer[i], HEX); 
+    DEBUG_SERIAL.print(F(", "));
+    if (read_len % 32 == 31) {
+      DEBUG_SERIAL.println();
+    }
+  }
+  DEBUG_SERIAL.println();
+#endif
+
   digitalWrite(_cs, HIGH);
   _spi->endTransaction();
 

examples/spi_registers/spi_registers.ino

@@ -0,0 +1,34 @@
+#include <Adafruit_BusIO_Register.h>
+#include <Adafruit_SPIDevice.h>
+
+#define SPIDEVICE_CS 10
+Adafruit_SPIDevice spi_dev = Adafruit_SPIDevice(SPIDEVICE_CS);
+
+void setup() {
+  while (!Serial) { delay(10); }
+  Serial.begin(115200);
+  Serial.println("SPI device register test");
+
+  if (!spi_dev.begin()) {
+    Serial.println("Could not initialize SPI device");
+    while (1);
+  }
+
+  Adafruit_BusIO_Register id_reg = Adafruit_BusIO_Register(&spi_dev, 0x0F, ADDRBIT8_HIGH_TOREAD);
+  uint8_t id;
+  id_reg.read(&id);
+  Serial.print("ID register = 0x"); Serial.println(id, HEX);
+
+  Adafruit_BusIO_Register thresh_reg = Adafruit_BusIO_Register(&spi_dev, 0x0C, ADDRBIT8_HIGH_TOREAD, 2, LSBFIRST);
+  uint16_t thresh;
+  thresh_reg.read(&thresh);
+  Serial.print("Initial threshold register = 0x"); Serial.println(thresh, HEX);
+
+  thresh_reg.write(~thresh);
+
+  Serial.print("Post threshold register = 0x"); Serial.println(thresh_reg.read(), HEX);
+}
+
+void loop() {
+  
+}