mcp2515: add support for mcp2515 CAN device

This commit is contained in:
akif999
2021-05-09 22:35:48 +09:00
committed by Ron Evans
parent d7f619ca21
commit 428db3cd12
5 changed files with 1267 additions and 2 deletions
+3 -1
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@@ -89,6 +89,8 @@ smoke-test:
@md5sum ./build/test.hex
tinygo build -size short -o ./build/test.hex -target=itsybitsy-m0 ./examples/mcp3008/main.go
@md5sum ./build/test.hex
tinygo build -size short -o ./build/test.hex -target=itsybitsy-m0 ./examples/mcp2515/main.go
@md5sum ./build/test.hex
tinygo build -size short -o ./build/test.hex -target=microbit ./examples/microbitmatrix/main.go
@md5sum ./build/test.hex
tinygo build -size short -o ./build/test.hex -target=itsybitsy-m0 ./examples/mma8653/main.go
@@ -194,7 +196,7 @@ DRIVERS = $(wildcard */)
NOTESTS = build examples flash semihosting pcd8544 shiftregister st7789 microphone mcp3008 gps microbitmatrix \
hcsr04 ssd1331 ws2812 thermistor apa102 easystepper ssd1351 ili9341 wifinina shifter hub75 \
hd44780 buzzer ssd1306 espat l9110x st7735 bmi160 l293x dht keypad4x4 max72xx p1am tone tm1637 \
pcf8563
pcf8563 mcp2515
TESTS = $(filter-out $(addsuffix /%,$(NOTESTS)),$(DRIVERS))
unit-test:
+2 -1
View File
@@ -52,7 +52,7 @@ func main() {
## Currently supported devices
The following 63 devices are supported.
The following 64 devices are supported.
| Device Name | Interface Type |
|----------|-------------|
@@ -92,6 +92,7 @@ The following 63 devices are supported.
| [MAX7219 & MAX7221 display driver](https://datasheets.maximintegrated.com/en/ds/MAX7219-MAX7221.pdf) | SPI |
| [MCP23017 port expander](https://ww1.microchip.com/downloads/en/DeviceDoc/20001952C.pdf) | I2C |
| [MCP3008 analog to digital converter (ADC)](http://ww1.microchip.com/downloads/en/DeviceDoc/21295d.pdf) | SPI |
| [MCP2515 Stand-Alone CAN Controller with SPI Interface](https://ww1.microchip.com/downloads/en/DeviceDoc/MCP2515-Family-Data-Sheet-DS20001801K.pdf) | SPI |
| [Microphone - PDM](https://cdn-learn.adafruit.com/assets/assets/000/049/977/original/MP34DT01-M.pdf) | I2S/PDM |
| [MMA8653 accelerometer](https://www.nxp.com/docs/en/data-sheet/MMA8653FC.pdf) | I2C |
| [MPU6050 accelerometer/gyroscope](https://store.invensense.com/datasheets/invensense/MPU-6050_DataSheet_V3%204.pdf) | I2C |
+55
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@@ -0,0 +1,55 @@
package main
import (
"fmt"
"machine"
"time"
"tinygo.org/x/drivers/mcp2515"
)
var (
spi = machine.SPI0
csPin = machine.D5
)
func main() {
spi.Configure(machine.SPIConfig{
Frequency: 115200,
SCK: machine.SPI0_SCK_PIN,
SDO: machine.SPI0_SDO_PIN,
SDI: machine.SPI0_SDI_PIN,
Mode: 0})
can := mcp2515.New(spi, csPin)
can.Configure()
err := can.Begin(mcp2515.CAN500kBps, mcp2515.Clock8MHz)
if err != nil {
failMessage(err.Error())
}
for {
err := can.Tx(0x111, 8, []byte{0x00, 0xAA, 0x55, 0xAA, 0x55, 0xAA, 0x55, 0xAA})
if err != nil {
failMessage(err.Error())
}
if can.Received() {
msg, err := can.Rx()
if err != nil {
failMessage(err.Error())
}
fmt.Printf("CAN-ID: %03X dlc: %d data: ", msg.ID, msg.Dlc)
for _, b := range msg.Data {
fmt.Printf("%02X ", b)
}
fmt.Print("\r\n")
}
time.Sleep(time.Millisecond * 500)
}
}
func failMessage(msg string) {
for {
println(msg)
time.Sleep(1 * time.Second)
}
}
+786
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@@ -0,0 +1,786 @@
// Package mcp2515 implements a driver for the MCP2515 CAN Controller.
//
// Datasheet: http://ww1.microchip.com/downloads/en/DeviceDoc/MCP2515-Stand-Alone-CAN-Controller-with-SPI-20001801J.pdf
//
// Reference: https://github.com/coryjfowler/MCP_CAN_lib
package mcp2515 // import "tinygo.org/x/drivers/mcp2515"
import (
"errors"
"fmt"
"machine"
"time"
"tinygo.org/x/drivers"
)
// Device wraps MCP2515 SPI CAN Module.
type Device struct {
spi SPI
cs machine.Pin
msg *CANMsg
mcpMode byte
}
// CANMsg stores CAN message fields.
type CANMsg struct {
ID uint32
Dlc uint8
Data []byte
Ext bool
Rtr bool
}
const (
bufferSize int = 64
)
// New returns a new MCP2515 driver. Pass in a fully configured SPI bus.
func New(b drivers.SPI, csPin machine.Pin) *Device {
d := &Device{
spi: SPI{
bus: b,
tx: make([]byte, 0, bufferSize),
rx: make([]byte, 0, bufferSize),
},
cs: csPin,
msg: &CANMsg{},
}
return d
}
// Configure sets up the device for communication.
func (d *Device) Configure() {
d.cs.Configure(machine.PinConfig{Mode: machine.PinOutput})
}
const beginTimeoutValue int = 10
// Begin starts the CAN controller.
func (d *Device) Begin(speed byte, clock byte) error {
timeOutCount := 0
for {
err := d.init(speed, clock)
if err == nil {
break
}
timeOutCount++
if timeOutCount >= beginTimeoutValue {
return err
}
}
return nil
}
// Received returns true if CAN message is received.
func (d *Device) Received() bool {
res, err := d.readStatus()
if err != nil {
panic(err)
}
// if RX STATUS INSTRUCTION result is not 0x00 (= No RX message)
// TODO: reconsider this logic
return (res & mcpStatRxifMask) != 0x00
}
// Rx returns received CAN message.
func (d *Device) Rx() (*CANMsg, error) {
err := d.readMsg()
return d.msg, err
}
// Tx transmits CAN Message.
func (d *Device) Tx(canid uint32, dlc uint8, data []byte) error {
// TODO: add ext, rtrBit, waitSent
timeoutCount := 0
var bufNum, res uint8
var err error
res = mcpAlltxbusy
for res == mcpAlltxbusy && (timeoutCount < timeoutvalue) {
if timeoutCount > 0 {
time.Sleep(time.Microsecond * 10)
}
bufNum, res, err = d.getNextFreeTxBuf()
if err != nil {
return err
}
timeoutCount++
}
if timeoutCount == timeoutvalue {
return fmt.Errorf("Tx: Tx timeout")
}
err = d.writeCANMsg(bufNum, canid, 0, 0, dlc, data)
if err != nil {
return err
}
return nil
}
func (d *Device) init(speed, clock byte) error {
err := d.Reset()
if err != nil {
return err
}
if err := d.setCANCTRLMode(modeConfig); err != nil {
return fmt.Errorf("setCANCTRLMode %s: ", err)
}
time.Sleep(time.Millisecond * 10)
// set baudrate
if err := d.configRate(speed, clock); err != nil {
return fmt.Errorf("configRate %s: ", err)
}
time.Sleep(time.Millisecond * 10)
if err := d.initCANBuffers(); err != nil {
return fmt.Errorf("initCANBuffers: %s ", err)
}
if err := d.setRegister(mcpCANINTE, mcpRX0IF|mcpRX1IF); err != nil {
return fmt.Errorf("setRegister: %s ", err)
}
if err := d.modifyRegister(mcpRXB0CTRL, mcpRxbRxMask|mcpRxbBuktMask, mcpRxbRxStdExt|mcpRxbBuktMask); err != nil {
return fmt.Errorf("modifyRegister: %s ", err)
}
if err := d.modifyRegister(mcpRXB1CTRL, mcpRxbRxMask, mcpRxbRxStdExt); err != nil {
return fmt.Errorf("modifyRegister: %s ", err)
}
if err := d.setMode(modeNormal); err != nil {
return fmt.Errorf("setMode %s: ", err)
}
time.Sleep(time.Millisecond * 10)
return nil
}
// Reset resets mcp2515.
func (d *Device) Reset() error {
d.cs.Low()
_, err := d.spi.readWrite(mcpReset)
d.cs.High()
// time.Sleep(time.Microsecond * 4)
if err != nil {
return err
}
time.Sleep(time.Millisecond * 10)
return nil
}
func (d *Device) setCANCTRLMode(newMode byte) error {
// If the chip is asleep and we want to change mode then a manual wake needs to be done
// This is done by setting the wake up interrupt flag
// This undocumented trick was found at https://github.com/mkleemann/can/blob/master/can_sleep_mcp2515.c
m, err := d.getMode()
if err != nil {
return err
}
if m == modeSleep && newMode != modeSleep {
r, err := d.readRegister(mcpCANINTE)
if err != nil {
return err
}
wakeIntEnabled := (r & mcpWAKIF) == 0x00
if !wakeIntEnabled {
d.modifyRegister(mcpCANINTE, mcpWAKIF, mcpWAKIF)
}
// Set wake flag (this does the actual waking up)
d.modifyRegister(mcpCANINTF, mcpWAKIF, mcpWAKIF)
// Wait for the chip to exit SLEEP and enter LISTENONLY mode.
// If the chip is not connected to a CAN bus (or the bus has no other powered nodes) it will sometimes trigger the wake interrupt as soon
// as it's put to sleep, but it will stay in SLEEP mode instead of automatically switching to LISTENONLY mode.
// In this situation the mode needs to be manually set to LISTENONLY.
if err := d.requestNewMode(modeListenOnly); err != nil {
return err
}
// Turn wake interrupt back off if it was originally off
if !wakeIntEnabled {
d.modifyRegister(mcpCANINTE, mcpWAKIF, 0)
}
}
// Clear wake flag
d.modifyRegister(mcpCANINTF, mcpWAKIF, 0)
return d.requestNewMode(newMode)
}
func (d *Device) setMode(opMode byte) error {
if opMode != modeSleep {
d.mcpMode = opMode
}
err := d.setCANCTRLMode(opMode)
if err != nil {
return err
}
return nil
}
func (d *Device) getMode() (byte, error) {
r, err := d.readRegister(mcpCANSTAT)
if err != nil {
return 0, err
}
return r & modeMask, nil
}
func (d *Device) configRate(speed, clock byte) error {
// TODO: add another baudrate
var cfg1, cfg2, cfg3 byte
set := true
switch clock {
case Clock16MHz:
switch speed {
case CAN500kBps:
cfg1 = mcp16mHz500kBpsCfg1
cfg2 = mcp16mHz500kBpsCfg2
cfg3 = mcp16mHz500kBpsCfg3
case CAN1000kBps:
cfg1 = mcp16mHz1000kBpsCfg1
cfg2 = mcp16mHz1000kBpsCfg2
cfg3 = mcp16mHz1000kBpsCfg3
default:
set = false
}
case Clock8MHz:
switch speed {
case CAN500kBps:
cfg1 = mcp8mHz500kBpsCfg1
cfg2 = mcp8mHz500kBpsCfg2
cfg3 = mcp8mHz500kBpsCfg3
case CAN1000kBps:
cfg1 = mcp8mHz1000kBpsCfg1
cfg2 = mcp8mHz1000kBpsCfg2
cfg3 = mcp8mHz1000kBpsCfg3
default:
set = false
}
default:
set = false
}
if !set {
return errors.New("invalid parameter")
}
if err := d.setRegister(mcpCNF1, cfg1); err != nil {
return err
}
if err := d.setRegister(mcpCNF2, cfg2); err != nil {
return err
}
if err := d.setRegister(mcpCNF3, cfg3); err != nil {
return err
}
return nil
}
func (d *Device) initCANBuffers() error {
a1 := byte(mcpTXB0CTRL)
a2 := byte(mcpTXB1CTRL)
a3 := byte(mcpTXB2CTRL)
for i := 0; i < 14; i++ {
if err := d.setRegister(a1, 0); err != nil {
return err
}
if err := d.setRegister(a2, 0); err != nil {
return err
}
if err := d.setRegister(a3, 0); err != nil {
return err
}
a1++
a2++
a3++
}
if err := d.setRegister(mcpRXB0CTRL, 0); err != nil {
return err
}
if err := d.setRegister(mcpRXB1CTRL, 0); err != nil {
return err
}
return nil
}
func (d *Device) readMsg() error {
status, err := d.readRxTxStatus()
if err != nil {
return err
}
if (status & mcpRX0IF) == 0x01 {
err := d.readRxBuffer(mcpReadRx0)
if err != nil {
return err
}
} else if (status & mcpRX1IF) == 0x02 {
err := d.readRxBuffer(mcpReadRx1)
if err != nil {
return err
}
} else {
return fmt.Errorf("readMsg: nothing is received")
}
return nil
}
func (d *Device) readRxBuffer(loadAddr uint8) error {
msg := d.msg
d.cs.Low()
defer d.cs.High()
_, err := d.spi.readWrite(loadAddr)
if err != nil {
return err
}
err = d.spi.read(4)
if err != nil {
return err
}
buf := d.spi.rx
msg.ID = uint32((uint32(buf[0]) << 3) + (uint32(buf[1]) >> 5))
msg.Ext = false
if (buf[1] & mcpTxbExideM) == mcpTxbExideM {
// extended id
msg.ID = uint32(uint32(msg.ID<<2) + uint32(buf[1]&0x03))
msg.ID = uint32(uint32(msg.ID<<8) + uint32(buf[2]))
msg.ID = uint32(uint32(msg.ID<<8) + uint32(buf[3]))
msg.Ext = true
}
err = d.spi.read(1)
if err != nil {
return err
}
msgSize := d.spi.rx[0]
msg.Dlc = uint8(msgSize & mcpDlcMask)
msg.Rtr = false
if (msgSize & mcpRtrMask) == 0x40 {
msg.Rtr = true
}
readLen := uint8(canMaxCharInMessage)
if msg.Dlc < canMaxCharInMessage {
readLen = msg.Dlc
}
err = d.spi.read(int(readLen))
if err != nil {
return err
}
msg.Data = d.spi.rx
return err
}
func (d *Device) getNextFreeTxBuf() (uint8, uint8, error) {
status, err := d.readStatus()
if err != nil {
return 0, mcpAlltxbusy, err
}
status &= mcpStatTxPendingMask
bufNum := uint8(0x00)
if status == mcpStatTxPendingMask {
return 0, mcpAlltxbusy, nil
}
for i := 0; i < int(mcpNTxbuffers-nReservedTx(0)); i++ {
if (status & txStatusPendingFlag(uint8(i))) == 0 {
bufNum = txCtrlReg(uint8(i)) + 1
d.modifyRegister(mcpCANINTF, txIfFlag(uint8(i)), 0)
return bufNum, mcp2515Ok, nil
}
}
return 0, mcpAlltxbusy, nil
}
func (d *Device) writeCANMsg(bufNum uint8, canid uint32, ext, rtrBit, dlc uint8, data []byte) error {
d.cs.Low()
defer d.cs.High()
_, err := d.spi.readWrite(txSidhToLoad(bufNum))
if err != nil {
return err
}
err = d.spi.clearBuffer(tx)
if err != nil {
return err
}
err = d.spi.setTxBufData(canid, ext, rtrBit, dlc, data)
if err != nil {
return err
}
err = d.spi.write()
if err != nil {
return err
}
// Since cs.Low and cs.High are executed in d.startTransmission,
// it is necessary to set cs.High once to separate the instruction of mcp2515.
d.cs.High()
err = d.startTransmission(bufNum)
if err != nil {
return err
}
return nil
}
func (s *SPI) setTxBufData(canid uint32, ext, rtrBit, dlc uint8, data []byte) error {
canid = canid & 0x0FFFF
if ext == 1 {
// TODO: add Extended ID
err := s.setTxData(0)
if err != nil {
return err
}
err = s.setTxData(0)
if err != nil {
return err
}
err = s.setTxData(0)
if err != nil {
return err
}
err = s.setTxData(0)
if err != nil {
return err
}
} else {
err := s.setTxData(byte(canid >> 3))
if err != nil {
return err
}
err = s.setTxData(byte((canid & 0x07) << 5))
if err != nil {
return err
}
err = s.setTxData(0)
if err != nil {
return err
}
err = s.setTxData(0)
if err != nil {
return err
}
}
if rtrBit == 1 {
dlc |= mcpRtrMask
} else {
dlc |= (0)
}
err := s.setTxData(dlc)
if err != nil {
return err
}
for _, d := range data {
err := s.setTxData(d)
if err != nil {
return err
}
}
return nil
}
func (d *Device) startTransmission(bufNum uint8) error {
d.cs.Low()
_, err := d.spi.readWrite(txSidhToRTS(bufNum))
d.cs.High()
if err != nil {
return err
}
return nil
}
func nReservedTx(number uint8) uint8 {
if number < mcpNTxbuffers {
return number
}
return mcpNTxbuffers - 1
}
func txStatusPendingFlag(i uint8) uint8 {
ret := uint8(0)
switch i {
case 0:
ret = mcpStatTx0Pending
case 1:
ret = mcpStatTx1Pending
case 2:
ret = mcpStatTx2Pending
}
return ret
}
func txCtrlReg(status uint8) uint8 {
ret := uint8(0)
switch status {
case 0:
ret = mcpTXB0CTRL
case 1:
ret = mcpTXB1CTRL
case 2:
ret = mcpTXB2CTRL
}
return ret
}
func txIfFlag(i uint8) uint8 {
ret := uint8(0)
switch i {
case 0:
ret = mcpTX0IF
case 1:
ret = mcpTX1IF
case 2:
ret = mcpTX2IF
}
return ret
}
func txSidhToSidh(i uint8) uint8 {
ret := uint8(0)
switch i {
case mcpTX0IF:
ret = mcpTXB0SIDH
case mcpTX1IF:
ret = mcpTXB1SIDH
case mcpTX2IF:
ret = mcpTXB2SIDH
}
return ret
}
func txSidhToRTS(i uint8) uint8 {
ret := uint8(0)
switch i {
case mcpTXB0SIDH:
ret = mcpRtsTx0
case mcpTXB1SIDH:
ret = mcpRtsTx1
case mcpTXB2SIDH:
ret = mcpRtsTx2
}
return ret
}
func txSidhToLoad(i uint8) uint8 {
ret := uint8(0)
switch i {
case mcpTXB0SIDH:
ret = mcpLoadTx0
case mcpTXB1SIDH:
ret = mcpLoadTx1
case mcpTXB2SIDH:
ret = mcpLoadTx2
}
return ret
}
func (d *Device) setRegister(addr, value byte) error {
d.cs.Low()
defer d.cs.High()
_, err := d.spi.readWrite(mcpWrite)
if err != nil {
return err
}
_, err = d.spi.readWrite(addr)
if err != nil {
return err
}
_, err = d.spi.readWrite(value)
if err != nil {
return err
}
// time.Sleep(time.Microsecond * 4)
return nil
}
func (d *Device) readRegister(addr byte) (byte, error) {
d.cs.Low()
defer d.cs.High()
_, err := d.spi.readWrite(mcpRead)
if err != nil {
return 0, err
}
_, err = d.spi.readWrite(addr)
if err != nil {
return 0, err
}
err = d.spi.read(1)
if err != nil {
return 0, err
}
// time.Sleep(time.Microsecond * 4)
return d.spi.rx[0], nil
}
func (d *Device) modifyRegister(addr, mask, data byte) error {
d.cs.Low()
defer d.cs.High()
_, err := d.spi.readWrite(mcpBitMod)
if err != nil {
return err
}
_, err = d.spi.readWrite(addr)
if err != nil {
return err
}
_, err = d.spi.readWrite(mask)
if err != nil {
return err
}
_, err = d.spi.readWrite(data)
if err != nil {
return err
}
// time.Sleep(time.Microsecond * 4)
return nil
}
func (d *Device) requestNewMode(newMode byte) error {
s := time.Now()
for {
err := d.modifyRegister(mcpCANCTRL, modeMask, newMode)
if err != nil {
return err
}
r, err := d.readRegister(mcpCANSTAT)
if err != nil {
return err
}
if r&modeMask == newMode {
return nil
} else if e := time.Now(); e.Sub(s) > 200*time.Millisecond {
return errors.New("requestNewMode max time expired")
}
}
}
func (d *Device) readStatus() (byte, error) {
d.cs.Low()
defer d.cs.High()
_, err := d.spi.readWrite(mcpReadStatus)
if err != nil {
return 0, err
}
err = d.spi.read(1)
if err != nil {
return 0, err
}
return d.spi.rx[0], nil
}
func (d *Device) readRxTxStatus() (byte, error) {
status, err := d.readStatus()
if err != nil {
return 0, err
}
ret := status & (mcpStatTxifMask | mcpStatRxifMask)
if (status & mcpStatTx0if) == 0x08 {
ret |= mcpTX0IF
}
if (status & mcpStatTx1if) == 0x20 {
ret |= mcpTX1IF
}
if (status & mcpStatTx2if) == 0x80 {
ret |= mcpTX2IF
}
ret |= ret & mcpStatRxifMask
return ret, nil
}
type SPI struct {
bus drivers.SPI
tx []byte
rx []byte
}
const (
tx = iota
rx
)
func (s *SPI) readWrite(w byte) (byte, error) {
return s.bus.Transfer(w)
}
func (s *SPI) read(readLength int) error {
err := s.clearBuffer(rx)
if err != nil {
return err
}
err = s.setBufferLength(readLength, rx)
if err != nil {
return err
}
return s.bus.Tx(nil, s.rx)
}
func (s *SPI) write() error {
return s.bus.Tx(s.tx, nil)
}
func (s *SPI) clearBuffer(dir int) error { return s.setBufferLength(0, dir) }
func (s *SPI) setBufferLength(length int, dir int) error {
if dir == tx {
if length > cap(s.tx) {
return fmt.Errorf("length is longer than capacity")
}
s.tx = s.tx[:length]
} else if dir == rx {
if length > cap(s.rx) {
return fmt.Errorf("length is longer than capacity")
}
s.rx = s.rx[:length]
} else {
return fmt.Errorf("invalid direction")
}
return nil
}
func (s *SPI) setTxData(data byte) error {
if len(s.tx) >= bufferSize {
return fmt.Errorf("cannot expand buffer (to avoid memory allocation)")
}
s.tx = append(s.tx, data)
return nil
}
func (d *Device) dumpMode() error {
m, err := d.getMode()
if err != nil {
return err
}
fmt.Printf("Mode: %02X\r\n", m)
return nil
}
func (d *Device) dumpRegister(addr byte) error {
r, err := d.readRegister(addr)
if err != nil {
return err
}
fmt.Printf("Register: %02X = %02X\r\n", addr, r)
return nil
}
+421
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@@ -0,0 +1,421 @@
// Package mcp2515 implements a driver for the MCP2515 CAN Controller.
//
// Datasheet: http://ww1.microchip.com/downloads/en/DeviceDoc/MCP2515-Stand-Alone-CAN-Controller-with-SPI-20001801J.pdf
//
package mcp2515 // import "tinygo.org/x/drivers/mcp2515"
const DebugEn = 0
const (
// begin mt
timeoutvalue = 50
mcpSidh = 0
mcpSidl = 1
mcpEid8 = 2
mcpEid0 = 3
mcpTxbExideM = 0x08 // in txbnsidl
mcpDlcMask = 0x0f //= 4 lsbits
mcpRtrMask = 0x40 // =(1<=<6) bit= 6
mcpRxbRxAny = 0x60
mcpRxbRxExt = 0x40
mcpRxbRxStd = 0x20
mcpRxbRxStdExt = 0x00
mcpRxbRxMask = 0x60
mcpRxbBuktMask = 1 << 2
// bits in the txbnctrl registers.
mcpTxbTxbufeM = 0x80
mcpTxbAbtfM = 0x40
mcpTxbMloaM = 0x20
mcpTxbTxerrM = 0x10
mcpTxbTxreqM = 0x08
mcpTxbTxieM = 0x04
mcpTxbTxp10M = 0x03
mcpTxbRtrM = 0x40 // in txbndlc
mcpRxbIdeM = 0x08 // in rxbnsidl
mcpRxbRtrM = 0x40 // in rxbndlc
mcpStatTxPendingMask = 0x54
mcpStatTx0Pending = 0x04
mcpStatTx1Pending = 0x10
mcpStatTx2Pending = 0x40
mcpStatTxifMask = 0xa8
mcpStatTx0if = 0x08
mcpStatTx1if = 0x20
mcpStatTx2if = 0x80
mcpStatRxifMask = 0x03
mcpStatRx0if = 1 << 0
mcpStatRx1if = 1 << 1
mcpEflgRx1ovr = 1 << 7
mcpEflgRx0ovr = 1 << 6
mcpEflgTxbo = 1 << 5
mcpEflgTxep = 1 << 4
mcpEflgRxep = 1 << 3
mcpEflgTxwar = 1 << 2
mcpEflgRxwar = 1 << 1
mcpEflgEwarn = 1 << 0
mcpEflgErrormask = 0xf8 //= 5 ms-bits
// define mcp2515 register addresses
mcpRXF0SIDH = 0x00
mcpRXF0SIDL = 0x01
mcpRXF0EID8 = 0x02
mcpRXF0EID0 = 0x03
mcpRXF1SIDH = 0x04
mcpRXF1SIDL = 0x05
mcpRXF1EID8 = 0x06
mcpRXF1EID0 = 0x07
mcpRXF2SIDH = 0x08
mcpRXF2SIDL = 0x09
mcpRXF2EID8 = 0x0a
mcpRXF2EID0 = 0x0b
mcpBFPCTRL = 0x0c
mcpTXRTSCTRl = 0x0d
mcpCANSTAT = 0x0e
mcpCANCTRL = 0x0f
mcpRXF3SIDH = 0x10
mcpRXF3SIDL = 0x11
mcpRXF3EID8 = 0x12
mcpRXF3EID0 = 0x13
mcpRXF4SIDH = 0x14
mcpRXF4SIDL = 0x15
mcpRXF4EID8 = 0x16
mcpRXF4EID0 = 0x17
mcpRXF5SIDH = 0x18
mcpRXF5SIDL = 0x19
mcpRXF5EID8 = 0x1a
mcpRXF5EID0 = 0x1b
mcpTEC = 0x1c
mcpREC = 0x1d
mcpRXM0SIDH = 0x20
mcpRXM0SIDL = 0x21
mcpRXM0EID8 = 0x22
mcpRXM0EID0 = 0x23
mcpRXM1SIDH = 0x24
mcpRXM1SIDL = 0x25
mcpRXM1EID8 = 0x26
mcpRXM1EID0 = 0x27
mcpCNF3 = 0x28
mcpCNF2 = 0x29
mcpCNF1 = 0x2a
mcpCANINTE = 0x2b
mcpCANINTF = 0x2c
mcpEFLG = 0x2d
mcpTXB0CTRL = 0x30
mcpTXB0SIDH = 0x31
mcpTXB1CTRL = 0x40
mcpTXB1SIDH = 0x41
mcpTXB2CTRL = 0x50
mcpTXB2SIDH = 0x51
mcpRXB0CTRL = 0x60
mcpRXB0SIDH = 0x61
mcpRXB1CTRL = 0x70
mcpRXB1SIDH = 0x71
mcpTxInt = 0x1c // enable all transmit interrup ts
mcpTx01Int = 0x0c // enable txb0 and txb1 interru pts
mcpRxInt = 0x03 // enable receive interrupts
mcpNoInt = 0x00 // disable all interrupts
mcpTx01Mask = 0x14
mcpTxMask = 0x54
// define spi instruction set
mcpWrite = 0x02
mcpRead = 0x03
mcpBitMod = 0x05
mcpLoadTx0 = 0x40
mcpLoadTx1 = 0x42
mcpLoadTx2 = 0x44
mcpRtsTx0 = 0x81
mcpRtsTx1 = 0x82
mcpRtsTx2 = 0x84
mcpRtsAll = 0x87
mcpReadRx0 = 0x90
mcpReadRx1 = 0x94
mcpReadStatus = 0xa0
mcpRxStatus = 0xb0
mcpReset = 0xc0
// canctrl register values
modeNormal = 0x00
modeSleep = 0x20
modeLoopBack = 0x40
modeListenOnly = 0x60
modeConfig = 0x80
modePowerUp = 0xe0
modeMask = 0xe0
abortTx = 0x10
modeOneShot = 0x08
clkoutEnable = 0x04
clkoutDisable = 0x00
clkoutPs1 = 0x00
clkoutPs2 = 0x01
clkoutPs4 = 0x02
clkoutPs8 = 0x03
// cnf1 register values
sjw1 = 0x00
sjw2 = 0x40
sjw3 = 0x80
sjw4 = 0xc0
// cnf2 register values
btlmode = 0x80
sample1x = 0x00
sample3x = 0x40
// cnf3 register values
sofEnable = 0x80
sofDisable = 0x00
wakfilEnable = 0x40
wakfilDisable = 0x00
// canintf register bits
mcpRX0IF = 0x01
mcpRX1IF = 0x02
mcpTX0IF = 0x04
mcpTX1IF = 0x08
mcpTX2IF = 0x10
mcpERRIF = 0x20
mcpWAKIF = 0x40
mcpMERRF = 0x80
// bfpctrl register bits
b1bfs = 0x20
b0bfs = 0x10
b1bfe = 0x08
b0bfe = 0x04
b1bfm = 0x02
b0bfm = 0x01
// txrtctrl register bits
b2rts = 0x20
b1rts = 0x10
b0rts = 0x08
b2rtsm = 0x04
b1rtsm = 0x02
b0rtsm = 0x01
// clock
Clock16MHz = 1
Clock8MHz = 2
// speed= 16m
mcp16mHz1000kBpsCfg1 = 0x00
mcp16mHz1000kBpsCfg2 = 0xd0
mcp16mHz1000kBpsCfg3 = 0x82
mcp16mHz500kBpsCfg1 = 0x00
mcp16mHz500kBpsCfg2 = 0xf0
mcp16mHz500kBpsCfg3 = 0x86
mcp16mHz250kBpsCfg1 = 0x41
mcp16mHz250kBpsCfg2 = 0xf1
mcp16mHz250kBpsCfg3 = 0x85
mcp16mHz200kBpsCfg1 = 0x01
mcp16mHz200kBpsCfg2 = 0xfa
mcp16mHz200kBpsCfg3 = 0x87
mcp16mHz125kBpsCfg1 = 0x03
mcp16mHz125kBpsCfg2 = 0xf0
mcp16mHz125kBpsCfg3 = 0x86
mcp16mHz100kBpsCfg1 = 0x03
mcp16mHz100kBpsCfg2 = 0xfa
mcp16mHz100kBpsCfg3 = 0x87
mcp16mHz95kBpsCfg1 = 0x03
mcp16mHz95kBpsCfg2 = 0xad
mcp16mHz95kBpsCfg3 = 0x07
mcp16mHz83k3BpsCfg1 = 0x03
mcp16mHz83k3BpsCfg2 = 0xbe
mcp16mHz83k3BpsCfg3 = 0x07
mcp16mHz80kBpsCfg1 = 0x03
mcp16mHz80kBpsCfg2 = 0xff
mcp16mHz80kBpsCfg3 = 0x87
mcp16mHz50kBpsCfg1 = 0x07
mcp16mHz50kBpsCfg2 = 0xfa
mcp16mHz50kBpsCfg3 = 0x87
mcp16mHz40kBpsCfg1 = 0x07
mcp16mHz40kBpsCfg2 = 0xff
mcp16mHz40kBpsCfg3 = 0x87
mcp16mHz33kBpsCfg1 = 0x09
mcp16mHz33kBpsCfg2 = 0xbe
mcp16mHz33kBpsCfg3 = 0x07
mcp16mHz31k25BpsCfg1 = 0x0f
mcp16mHz31k25BpsCfg2 = 0xf1
mcp16mHz31k25BpsCfg3 = 0x85
mcp16mHz25kBpsCfg1 = 0x0f
mcp16mHz25kBpsCfg2 = 0xba
mcp16mHz25kBpsCfg3 = 0x07
mcp16mHz20kBpsCfg1 = 0x0f
mcp16mHz20kBpsCfg2 = 0xff
mcp16mHz20kBpsCfg3 = 0x87
mcp16mHz10kBpsCfg1 = 0x1f
mcp16mHz10kBpsCfg2 = 0xff
mcp16mHz10kBpsCfg3 = 0x87
mcp16mHz5kBpsCfg1 = 0x3f
mcp16mHz5kBpsCfg2 = 0xff
mcp16mHz5kBpsCfg3 = 0x87
mcp16mHz666kBpsCfg1 = 0x00
mcp16mHz666kBpsCfg2 = 0xa0
mcp16mHz666kBpsCfg3 = 0x04
// speed= 8m
mcp8mHz1000kBpsCfg1 = 0x00
mcp8mHz1000kBpsCfg2 = 0x80
mcp8mHz1000kBpsCfg3 = 0x00
mcp8mHz500kBpsCfg1 = 0x00
mcp8mHz500kBpsCfg2 = 0x90
mcp8mHz500kBpsCfg3 = 0x02
mcp8mHz250kBpsCfg1 = 0x00
mcp8mHz250kBpsCfg2 = 0xb1
mcp8mHz250kBpsCfg3 = 0x05
mcp8mHz200kBpsCfg1 = 0x00
mcp8mHz200kBpsCfg2 = 0xb4
mcp8mHz200kBpsCfg3 = 0x06
mcp8mHz125kBpsCfg1 = 0x01
mcp8mHz125kBpsCfg2 = 0xb1
mcp8mHz125kBpsCfg3 = 0x05
mcp8mHz100kBpsCfg1 = 0x01
mcp8mHz100kBpsCfg2 = 0xb4
mcp8mHz100kBpsCfg3 = 0x06
mcp8mHz80kBpsCfg1 = 0x01
mcp8mHz80kBpsCfg2 = 0xbf
mcp8mHz80kBpsCfg3 = 0x07
mcp8mHz50kBpsCfg1 = 0x03
mcp8mHz50kBpsCfg2 = 0xb4
mcp8mHz50kBpsCfg3 = 0x06
mcp8mHz40kBpsCfg1 = 0x03
mcp8mHz40kBpsCfg2 = 0xbf
mcp8mHz40kBpsCfg3 = 0x07
mcp8mHz31k25BpsCfg1 = 0x07
mcp8mHz31k25BpsCfg2 = 0xa4
mcp8mHz31k25BpsCfg3 = 0x04
mcp8mHz20kBpsCfg1 = 0x07
mcp8mHz20kBpsCfg2 = 0xbf
mcp8mHz20kBpsCfg3 = 0x07
mcp8mHz10kBpsCfg1 = 0x0f
mcp8mHz10kBpsCfg2 = 0xbf
mcp8mHz10kBpsCfg3 = 0x07
mcp8mHz5kBpsCfg1 = 0x1f
mcp8mHz5kBpsCfg2 = 0xbf
mcp8mHz5kBpsCfg3 = 0x07
mcp16mHz47kBpsCfg1 = 0x06
mcp16mHz47kBpsCfg2 = 0xbe
mcp16mHz47kBpsCfg3 = 0x07
mcpdebug = 0
mcpdebugTxbuf = 0
mcpNTxbuffers = 3
mcpRxbuf0 = 0x61
mcpRxbuf1 = 0x71
mcp2515Ok = 0
mcp2515Fail = 1
mcpAlltxbusy = 2
candebug = 1
canuseloop = 0
cansendtimeout = 200 // milliseconds
mcpPinHiz = 0
mcpPinInt = 1
mcpPinOut = 2
mcpPinIn = 3
mcpRx0bf = 0
mcpRx1bf = 1
mcpTx0rts = 2
mcpTx1rts = 3
mcpTx2rts = 4
// initial value of gcanautoprocess
canautoprocess = 1
canautoon = 1
canautooff = 0
canStdid = 0
canExtid = 1
candefaultident = 0x55cc
candefaultidentext = 1
CAN5kBps = 1
CAN10kBps = 2
CAN20kBps = 3
CAN25kBps = 4
CAN31k25Bps = 5
CAN33kBps = 6
CAN40kBps = 7
CAN50kBps = 8
CAN80kBps = 9
CAN83k3Bps = 10
CAN95kBps = 11
CAN100kBps = 12
CAN125kBps = 13
CAN200kBps = 14
CAN250kBps = 15
CAN500kBps = 16
CAN666kBps = 17
CAN1000kBps = 18
CAN47kBps = 19
canOk = 0
canFailinit = 1
canFailtx = 2
canMsgavail = 3
canNomsg = 4
canCtrlerror = 5
canGettxbftimeout = 6
canSendmsgtimeout = 7
canFail = 0xff
canMaxCharInMessage = 8
)