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Port SPISettings to Teensy 3.x

main
PaulStoffregen 10 years ago
parent
2535e00fd7
commit
05cd3c17cf
2 changed files with 134 additions and 4 deletions
Split View Show Diff Stats
  1. +49
    -1
      SPI.cpp
  2. +85
    -3
      SPI.h

+ 49
- 1
SPI.cpp View File

@@ -19,6 +19,7 @@ uint8_t SPIClass::interruptSave = 0;

void SPIClass::begin()
{
#if defined(__AVR__)
// Set SS to high so a connected chip will be "deselected" by default
digitalWrite(SS, HIGH);

@@ -39,14 +40,25 @@ void SPIClass::begin()
// clocking in a single bit since the lines go directly
// from "input" to SPI control.
// http://code.google.com/p/arduino/issues/detail?id=888
#ifdef __AVR__
pinMode(SCK, OUTPUT);
pinMode(MOSI, OUTPUT);
#elif defined(__arm__) && defined(TEENSYDUINO)
SIM_SCGC6 |= SIM_SCGC6_SPI0;
SPI0_MCR = SPI_MCR_MDIS | SPI_MCR_HALT | SPI_MCR_PCSIS(0x1F);
SPI0_CTAR0 = SPI_CTAR_FMSZ(7) | SPI_CTAR_PBR(0) | SPI_CTAR_BR(1) | SPI_CTAR_CSSCK(1);
SPI0_CTAR1 = SPI_CTAR_FMSZ(15) | SPI_CTAR_PBR(0) | SPI_CTAR_BR(1) | SPI_CTAR_CSSCK(1);
SPI0_MCR = SPI_MCR_MSTR | SPI_MCR_PCSIS(0x1F);
SPCR.enable_pins(); // pins managed by SPCRemulation in avr_emulation.h
#endif
}

void SPIClass::end() {
#if defined(__AVR__)
SPCR &= ~_BV(SPE);
#elif defined(__arm__) && defined(TEENSYDUINO)
SPCR.disable_pins();
SPI0_MCR = SPI_MCR_MDIS | SPI_MCR_HALT | SPI_MCR_PCSIS(0x1F);
#endif
}

void SPIClass::usingInterrupt(uint8_t interruptNumber)
@@ -91,3 +103,39 @@ void SPIClass::usingInterrupt(uint8_t interruptNumber)
interrupts();
}


#if defined(__arm__) && defined(TEENSYDUINO)
const uint16_t SPISettings::ctar_div_table[23] = {
2, 3, 4, 5, 6, 8, 10, 12, 16, 20, 24, 32, 40,
56, 64, 96, 128, 192, 256, 384, 512, 640, 768
};
const uint32_t SPISettings::ctar_clock_table[23] = {
SPI_CTAR_PBR(0) | SPI_CTAR_BR(0) | SPI_CTAR_DBR | SPI_CTAR_CSSCK(0),
SPI_CTAR_PBR(1) | SPI_CTAR_BR(0) | SPI_CTAR_DBR | SPI_CTAR_CSSCK(0),
SPI_CTAR_PBR(0) | SPI_CTAR_BR(0) | SPI_CTAR_CSSCK(0),
SPI_CTAR_PBR(2) | SPI_CTAR_BR(0) | SPI_CTAR_DBR | SPI_CTAR_CSSCK(0),
SPI_CTAR_PBR(1) | SPI_CTAR_BR(0) | SPI_CTAR_CSSCK(0),
SPI_CTAR_PBR(0) | SPI_CTAR_BR(1) | SPI_CTAR_CSSCK(1),
SPI_CTAR_PBR(2) | SPI_CTAR_BR(0) | SPI_CTAR_CSSCK(0),
SPI_CTAR_PBR(1) | SPI_CTAR_BR(1) | SPI_CTAR_CSSCK(1),
SPI_CTAR_PBR(0) | SPI_CTAR_BR(3) | SPI_CTAR_CSSCK(2),
SPI_CTAR_PBR(2) | SPI_CTAR_BR(1) | SPI_CTAR_CSSCK(0),
SPI_CTAR_PBR(1) | SPI_CTAR_BR(3) | SPI_CTAR_CSSCK(2),
SPI_CTAR_PBR(0) | SPI_CTAR_BR(4) | SPI_CTAR_CSSCK(3),
SPI_CTAR_PBR(2) | SPI_CTAR_BR(3) | SPI_CTAR_CSSCK(2),
SPI_CTAR_PBR(3) | SPI_CTAR_BR(3) | SPI_CTAR_CSSCK(2),
SPI_CTAR_PBR(0) | SPI_CTAR_BR(5) | SPI_CTAR_CSSCK(4),
SPI_CTAR_PBR(1) | SPI_CTAR_BR(5) | SPI_CTAR_CSSCK(4),
SPI_CTAR_PBR(0) | SPI_CTAR_BR(6) | SPI_CTAR_CSSCK(5),
SPI_CTAR_PBR(1) | SPI_CTAR_BR(6) | SPI_CTAR_CSSCK(5),
SPI_CTAR_PBR(0) | SPI_CTAR_BR(7) | SPI_CTAR_CSSCK(6),
SPI_CTAR_PBR(1) | SPI_CTAR_BR(7) | SPI_CTAR_CSSCK(6),
SPI_CTAR_PBR(0) | SPI_CTAR_BR(8) | SPI_CTAR_CSSCK(7),
SPI_CTAR_PBR(2) | SPI_CTAR_BR(7) | SPI_CTAR_CSSCK(6),
SPI_CTAR_PBR(1) | SPI_CTAR_BR(8) | SPI_CTAR_CSSCK(7)
};
#endif





+ 85
- 3
SPI.h View File

@@ -63,6 +63,7 @@ private:
void init_MightInline(uint32_t clock, uint8_t bitOrder, uint8_t dataMode) {
init_AlwaysInline(clock, bitOrder, dataMode);
}
#if defined(__AVR__)
void init_AlwaysInline(uint32_t clock, uint8_t bitOrder, uint8_t dataMode)
__attribute__((__always_inline__)) {
// Clock settings are defined as follows. Note that this shows SPI2X
@@ -127,6 +128,78 @@ private:
}
uint8_t spcr;
uint8_t spsr;
#elif defined(__arm__) && defined(TEENSYDUINO)
void init_AlwaysInline(uint32_t clock, uint8_t bitOrder, uint8_t dataMode)
__attribute__((__always_inline__)) {
uint32_t t, c = SPI_CTAR_FMSZ(7);
if (bitOrder == LSBFIRST) c |= SPI_CTAR_LSBFE;
if (__builtin_constant_p(clock)) {
if (clock >= F_BUS / 2) {
t = SPI_CTAR_PBR(0) | SPI_CTAR_BR(0) | SPI_CTAR_DBR | SPI_CTAR_CSSCK(0);
} else if (clock >= F_BUS / 3) {
t = SPI_CTAR_PBR(1) | SPI_CTAR_BR(0) | SPI_CTAR_DBR | SPI_CTAR_CSSCK(0);
} else if (clock >= F_BUS / 4) {
t = SPI_CTAR_PBR(0) | SPI_CTAR_BR(0) | SPI_CTAR_CSSCK(0);
} else if (clock >= F_BUS / 5) {
t = SPI_CTAR_PBR(2) | SPI_CTAR_BR(0) | SPI_CTAR_DBR | SPI_CTAR_CSSCK(0);
} else if (clock >= F_BUS / 6) {
t = SPI_CTAR_PBR(1) | SPI_CTAR_BR(0) | SPI_CTAR_CSSCK(0);
} else if (clock >= F_BUS / 8) {
t = SPI_CTAR_PBR(0) | SPI_CTAR_BR(1) | SPI_CTAR_CSSCK(1);
} else if (clock >= F_BUS / 10) {
t = SPI_CTAR_PBR(2) | SPI_CTAR_BR(0) | SPI_CTAR_CSSCK(0);
} else if (clock >= F_BUS / 12) {
t = SPI_CTAR_PBR(1) | SPI_CTAR_BR(1) | SPI_CTAR_CSSCK(1);
} else if (clock >= F_BUS / 16) {
t = SPI_CTAR_PBR(0) | SPI_CTAR_BR(3) | SPI_CTAR_CSSCK(2);
} else if (clock >= F_BUS / 20) {
t = SPI_CTAR_PBR(2) | SPI_CTAR_BR(1) | SPI_CTAR_CSSCK(0);
} else if (clock >= F_BUS / 24) {
t = SPI_CTAR_PBR(1) | SPI_CTAR_BR(3) | SPI_CTAR_CSSCK(2);
} else if (clock >= F_BUS / 32) {
t = SPI_CTAR_PBR(0) | SPI_CTAR_BR(4) | SPI_CTAR_CSSCK(3);
} else if (clock >= F_BUS / 40) {
t = SPI_CTAR_PBR(2) | SPI_CTAR_BR(3) | SPI_CTAR_CSSCK(2);
} else if (clock >= F_BUS / 56) {
t = SPI_CTAR_PBR(3) | SPI_CTAR_BR(3) | SPI_CTAR_CSSCK(2);
} else if (clock >= F_BUS / 64) {
t = SPI_CTAR_PBR(0) | SPI_CTAR_BR(5) | SPI_CTAR_CSSCK(4);
} else if (clock >= F_BUS / 96) {
t = SPI_CTAR_PBR(1) | SPI_CTAR_BR(5) | SPI_CTAR_CSSCK(4);
} else if (clock >= F_BUS / 128) {
t = SPI_CTAR_PBR(0) | SPI_CTAR_BR(6) | SPI_CTAR_CSSCK(5);
} else if (clock >= F_BUS / 192) {
t = SPI_CTAR_PBR(1) | SPI_CTAR_BR(6) | SPI_CTAR_CSSCK(5);
} else if (clock >= F_BUS / 256) {
t = SPI_CTAR_PBR(0) | SPI_CTAR_BR(7) | SPI_CTAR_CSSCK(6);
} else if (clock >= F_BUS / 384) {
t = SPI_CTAR_PBR(1) | SPI_CTAR_BR(7) | SPI_CTAR_CSSCK(6);
} else if (clock >= F_BUS / 512) {
t = SPI_CTAR_PBR(0) | SPI_CTAR_BR(8) | SPI_CTAR_CSSCK(7);
} else if (clock >= F_BUS / 640) {
t = SPI_CTAR_PBR(2) | SPI_CTAR_BR(7) | SPI_CTAR_CSSCK(6);
} else { /* F_BUS / 768 */
t = SPI_CTAR_PBR(1) | SPI_CTAR_BR(8) | SPI_CTAR_CSSCK(7);
}
} else {
for (uint32_t i=0; i<23; i++) {
t = ctar_clock_table[i];
if (clock >= F_BUS / ctar_div_table[i]) break;
}
}
if (dataMode & 0x08) {
c |= SPI_CTAR_CPOL;
}
if (dataMode & 0x04) {
c |= SPI_CTAR_CPHA;
t = (t & 0xFFFF0FFF) | ((t & 0xF000) >> 4);
}
ctar = c | t;
}
static const uint16_t ctar_div_table[23];
static const uint32_t ctar_clock_table[23];
uint32_t ctar;
#endif
friend class SPIClass;
};

@@ -143,7 +216,7 @@ public:
// with attachInterrupt. If SPI is used from a different interrupt
// (eg, a timer), interruptNumber should be 255.
static void usingInterrupt(uint8_t interruptNumber);
#if defined(__arm__) && defined(CORE_TEENSY)
#if defined(__arm__) && defined(TEENSYDUINO)
static void usingInterrupt(IRQ_NUMBER_t interruptName);
#endif

@@ -163,12 +236,21 @@ public:
cli();
}
}
#if defined(__AVR__)
SPCR = settings.spcr;
SPSR = settings.spsr;
#elif defined(__arm__) && defined(TEENSYDUINO)
if (SPI0_CTAR0 != settings.ctar) {
SPI0_MCR = SPI_MCR_MDIS | SPI_MCR_HALT | SPI_MCR_PCSIS(0x1F);
SPI0_CTAR0 = settings.ctar;
SPI0_CTAR1 = settings.ctar | SPI_CTAR_FMSZ(7);
SPI0_MCR = SPI_MCR_MSTR | SPI_MCR_PCSIS(0x1F);
}
#endif
}

// Write to the SPI bus (MOSI pin) and also receive (MISO pin)
inline static byte transfer(byte data) {
inline static uint8_t transfer(uint8_t data) {
SPDR = data;
asm volatile("nop");
while (!(SPSR & _BV(SPIF))) ; // wait
@@ -230,7 +312,7 @@ public:
inline static void attachInterrupt() { SPCR |= _BV(SPIE); }
inline static void detachInterrupt() { SPCR &= ~_BV(SPIE); }

#if defined(__arm__) && defined(CORE_TEENSY)
#if defined(__arm__) && defined(TEENSYDUINO)
inline void setMOSI(uint8_t pin) __attribute__((always_inline)) { SPCR.setMOSI(pin); }
inline void setMISO(uint8_t pin) __attribute__((always_inline)) { SPCR.setMISO(pin); }
inline void setSCK(uint8_t pin) __attribute__((always_inline)) { SPCR.setSCK(pin); }

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