Allow use of EPD displays on secondary SPI (#18)

* allow use of EPD displays on secondary SPI

* fix comment indent

Co-authored-by: Joey Castillo <[email protected]>

Author: 2 people

Adafruit_EPD.cpp

@@ -104,15 +104,17 @@ Adafruit_EPD::Adafruit_EPD(int width, int height, int8_t spi_mosi,
     @param CS the chip select pin to use
     @param SRCS the SRAM chip select pin to use
     @param BUSY the busy pin to use
+    @param spi the SPI bus to use
 */
 /**************************************************************************/
 Adafruit_EPD::Adafruit_EPD(int width, int height, int8_t DC, int8_t RST,
-                           int8_t CS, int8_t SRCS, int8_t BUSY)
+                           int8_t CS, int8_t SRCS, int8_t BUSY, SPIClass *spi)
     : Adafruit_GFX(width, height), sram(SRCS) {
   _cs_pin = CS;
   _reset_pin = RST;
   _dc_pin = DC;
   _busy_pin = BUSY;
+  _spi = spi;
   if (SRCS >= 0) {
     use_sram = true;
   } else {
@@ -180,9 +182,9 @@ void Adafruit_EPD::begin(bool reset) {
     mosipinmask = digitalPinToBitMask(_sid_pin);
 #endif
   } else {
-    SPI.begin();
+    _spi->begin();
 #ifndef SPI_HAS_TRANSACTION
-    SPI.setClockDivider(4);
+    _spi->setClockDivider(4);
 #endif
   }
 
@@ -579,11 +581,11 @@ uint8_t Adafruit_EPD::SPItransfer(uint8_t d) {
     if (singleByteTxns) {
       uint8_t b;
       csLow();
-      b = SPI.transfer(d);
+      b = _spi->transfer(d);
       csHigh();
       return b;
     } else
-      return SPI.transfer(d);
+      return _spi->transfer(d);
   } else {
     // TODO: return read data for software SPI
     for (uint8_t bit = 0x80; bit; bit >>= 1) {
@@ -614,7 +616,7 @@ uint8_t Adafruit_EPD::SPItransfer(uint8_t d) {
 /**************************************************************************/
 void Adafruit_EPD::csHigh() {
 #ifdef SPI_HAS_TRANSACTION
-  SPI.endTransaction();
+  _spi->endTransaction();
   _isInTransaction = false;
 #endif
 #ifdef HAVE_PORTREG
@@ -632,7 +634,7 @@ void Adafruit_EPD::csHigh() {
 void Adafruit_EPD::csLow() {
 #ifdef SPI_HAS_TRANSACTION
   if (!_isInTransaction) {
-    SPI.beginTransaction(SPISettings(4000000, MSBFIRST, SPI_MODE0));
+    _spi->beginTransaction(SPISettings(4000000, MSBFIRST, SPI_MODE0));
     _isInTransaction = true;
   }
 #endif

Adafruit_EPD.h

@@ -88,7 +88,7 @@ class Adafruit_EPD : public Adafruit_GFX {
                int8_t RST, int8_t CS, int8_t SRCS, int8_t MISO,
                int8_t BUSY = -1);
   Adafruit_EPD(int width, int height, int8_t DC, int8_t RST, int8_t CS,
-               int8_t SRCS, int8_t BUSY = -1);
+               int8_t SRCS, int8_t BUSY = -1, SPIClass *spi = &SPI);
   ~Adafruit_EPD();
 
   void begin(bool reset = true);
@@ -148,6 +148,7 @@ class Adafruit_EPD : public Adafruit_GFX {
       _reset_pin,               ///< reset pin
       _cs_pin,                  ///< chip select pin
       _busy_pin;                ///< busy pin
+  SPIClass *_spi = NULL;        ///< SPI object
   static bool _isInTransaction; ///< true if SPI bus is in trasnfer state
   bool singleByteTxns;   ///< if true CS will go high after every data byte
                          ///< transferred

Adafruit_MCPSRAM.cpp

@@ -26,10 +26,12 @@ Adafruit_MCPSRAM::Adafruit_MCPSRAM(int8_t mosi, int8_t miso, int8_t sck,
 /*!
     @brief  Class constructor when using hardware SPI
                 @param cs chip select pin
+                @param spi the SPI bus to use
 */
 /**************************************************************************/
-Adafruit_MCPSRAM::Adafruit_MCPSRAM(int8_t cs) {
+Adafruit_MCPSRAM::Adafruit_MCPSRAM(int8_t cs, SPIClass *spi) {
   _cs = cs;
+  _spi = spi;
   hwSPI = true;
 }
 
@@ -60,17 +62,17 @@ void Adafruit_MCPSRAM::begin() {
 #endif
   }
   if (hwSPI) {
-    SPI.begin();
+    _spi->begin();
 #ifndef SPI_HAS_TRANSACTION
-    SPI.setClockDivider(4);
+    _spi->setClockDivider(4);
 #endif
   }
 
   csLow();
 
   for (int i = 0; i < 3; i++) {
     if (hwSPI) {
-      (void)SPI.transfer(0xFF);
+      (void)_spi->transfer(0xFF);
     } else {
       for (uint8_t bit = 0x80; bit; bit >>= 1) {
 #ifdef HAVE_PORTREG
@@ -119,7 +121,7 @@ void Adafruit_MCPSRAM::write(uint16_t addr, uint8_t *buf, uint16_t num,
     uint8_t d = cmdbuf[i];
 
     if (hwSPI) {
-      (void)SPI.transfer(d);
+      (void)_spi->transfer(d);
     } else {
       for (uint8_t bit = 0x80; bit; bit >>= 1) {
 #ifdef HAVE_PORTREG
@@ -149,7 +151,7 @@ void Adafruit_MCPSRAM::write(uint16_t addr, uint8_t *buf, uint16_t num,
     uint8_t d = buf[i];
 
     if (hwSPI) {
-      (void)SPI.transfer(d);
+      (void)_spi->transfer(d);
     } else {
       for (uint8_t bit = 0x80; bit; bit >>= 1) {
 #ifdef HAVE_PORTREG
@@ -197,7 +199,7 @@ void Adafruit_MCPSRAM::read(uint16_t addr, uint8_t *buf, uint16_t num,
     uint8_t d = cmdbuf[i];
 
     if (hwSPI) {
-      (void)SPI.transfer(d);
+      (void)_spi->transfer(d);
     } else {
       for (uint8_t bit = 0x80; bit; bit >>= 1) {
 #ifdef HAVE_PORTREG
@@ -225,7 +227,7 @@ void Adafruit_MCPSRAM::read(uint16_t addr, uint8_t *buf, uint16_t num,
   for (int i = 0; i < num; i++) {
 
     if (hwSPI) {
-      buf[i] = SPI.transfer(0x00);
+      buf[i] = _spi->transfer(0x00);
     } else {
       for (uint8_t bit = 0x80; bit; bit >>= 1) {
 #ifdef HAVE_PORTREG
@@ -320,7 +322,7 @@ void Adafruit_MCPSRAM::erase(uint16_t addr, uint16_t length, uint8_t val) {
     uint8_t d = cmdbuf[i];
 
     if (hwSPI) {
-      (void)SPI.transfer(d);
+      (void)_spi->transfer(d);
     } else {
       for (uint8_t bit = 0x80; bit; bit >>= 1) {
 #ifdef HAVE_PORTREG
@@ -348,7 +350,7 @@ void Adafruit_MCPSRAM::erase(uint16_t addr, uint16_t length, uint8_t val) {
     uint8_t d = val;
 
     if (hwSPI) {
-      (void)SPI.transfer(d);
+      (void)_spi->transfer(d);
     } else {
       for (uint8_t bit = 0x80; bit; bit >>= 1) {
 #ifdef HAVE_PORTREG
@@ -380,7 +382,7 @@ void Adafruit_MCPSRAM::erase(uint16_t addr, uint16_t length, uint8_t val) {
 /**************************************************************************/
 void Adafruit_MCPSRAM::csHigh() {
 #ifdef SPI_HAS_TRANSACTION
-  SPI.endTransaction();
+  _spi->endTransaction();
 #endif
 #ifdef HAVE_PORTREG
   *csport |= cspinmask;
@@ -396,7 +398,7 @@ void Adafruit_MCPSRAM::csHigh() {
 /**************************************************************************/
 void Adafruit_MCPSRAM::csLow() {
 #ifdef SPI_HAS_TRANSACTION
-  SPI.beginTransaction(SPISettings(4000000, MSBFIRST, SPI_MODE0));
+  _spi->beginTransaction(SPISettings(4000000, MSBFIRST, SPI_MODE0));
 #endif
 #ifdef HAVE_PORTREG
   *csport &= ~cspinmask;

Adafruit_MCPSRAM.h

@@ -1,4 +1,5 @@
 #include <Arduino.h>
+#include <SPI.h>
 
 #define MCPSRAM_READ 0x03  ///< read command
 #define MCPSRAM_WRITE 0x02 ///< write command
@@ -15,7 +16,7 @@
 class Adafruit_MCPSRAM {
 public:
   Adafruit_MCPSRAM(int8_t mosi, int8_t miso, int8_t sck, int8_t cs);
-  Adafruit_MCPSRAM(int8_t cs);
+  Adafruit_MCPSRAM(int8_t cs, SPIClass *spi = &SPI);
   ~Adafruit_MCPSRAM() {}
 
   void begin();
@@ -42,4 +43,5 @@ class Adafruit_MCPSRAM {
   PortMask mosipinmask, clkpinmask, cspinmask, misopinmask;
 #endif
   int8_t _cs, _mosi, _miso, _sck;
+  SPIClass *_spi = NULL;
 };