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Tasmota/lib/lib_basic/OneWire-Stickbreaker/OneWire.h

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#ifndef OneWire_h
#define OneWire_h
#include <inttypes.h>
#if defined(__AVR__)
#include <util/crc16.h>
#endif
#if ARDUINO >= 100
#include "Arduino.h" // for delayMicroseconds, digitalPinToBitMask, etc
#else
#include "WProgram.h" // for delayMicroseconds
#include "pins_arduino.h" // for digitalPinToBitMask, etc
#endif
// You can exclude certain features from OneWire. In theory, this
// might save some space. In practice, the compiler automatically
// removes unused code (technically, the linker, using -fdata-sections
// and -ffunction-sections when compiling, and Wl,--gc-sections
// when linking), so most of these will not result in any code size
// reduction. Well, unless you try to use the missing features
// and redesign your program to not need them! ONEWIRE_CRC8_TABLE
// is the exception, because it selects a fast but large algorithm
// or a small but slow algorithm.
// you can exclude onewire_search by defining that to 0
#ifndef ONEWIRE_SEARCH
#define ONEWIRE_SEARCH 1
#endif
// You can exclude CRC checks altogether by defining this to 0
#ifndef ONEWIRE_CRC
#define ONEWIRE_CRC 1
#endif
// Select the table-lookup method of computing the 8-bit CRC
// by setting this to 1. The lookup table enlarges code size by
// about 250 bytes. It does NOT consume RAM (but did in very
// old versions of OneWire). If you disable this, a slower
// but very compact algorithm is used.
#ifndef ONEWIRE_CRC8_TABLE
#define ONEWIRE_CRC8_TABLE 0
#endif
// You can allow 16-bit CRC checks by defining this to 1
// (Note that ONEWIRE_CRC must also be 1.)
#ifndef ONEWIRE_CRC16
#define ONEWIRE_CRC16 1
#endif
#ifndef FALSE
#define FALSE 0
#endif
#ifndef TRUE
#define TRUE 1
#endif
// Platform specific I/O definitions
#if defined(__AVR__)
#define PIN_TO_BASEREG(pin) (portInputRegister(digitalPinToPort(pin)))
#define PIN_TO_BITMASK(pin) (digitalPinToBitMask(pin))
#define IO_REG_TYPE uint8_t
#define IO_REG_BASE_ATTR asm("r30")
#define IO_REG_MASK_ATTR
#define DIRECT_READ(base, mask) (((*(base)) & (mask)) ? 1 : 0)
#define DIRECT_MODE_INPUT(base, mask) ((*((base)+1)) &= ~(mask))
#define DIRECT_MODE_OUTPUT(base, mask) ((*((base)+1)) |= (mask))
#define DIRECT_WRITE_LOW(base, mask) ((*((base)+2)) &= ~(mask))
#define DIRECT_WRITE_HIGH(base, mask) ((*((base)+2)) |= (mask))
#elif defined(__MK20DX128__) || defined(__MK20DX256__) || defined(__MK66FX1M0__) || defined(__MK64FX512__)
#define PIN_TO_BASEREG(pin) (portOutputRegister(pin))
#define PIN_TO_BITMASK(pin) (1)
#define IO_REG_TYPE uint8_t
#define IO_REG_BASE_ATTR
#define IO_REG_MASK_ATTR __attribute__ ((unused))
#define DIRECT_READ(base, mask) (*((base)+512))
#define DIRECT_MODE_INPUT(base, mask) (*((base)+640) = 0)
#define DIRECT_MODE_OUTPUT(base, mask) (*((base)+640) = 1)
#define DIRECT_WRITE_LOW(base, mask) (*((base)+256) = 1)
#define DIRECT_WRITE_HIGH(base, mask) (*((base)+128) = 1)
#elif defined(__MKL26Z64__)
#define PIN_TO_BASEREG(pin) (portOutputRegister(pin))
#define PIN_TO_BITMASK(pin) (digitalPinToBitMask(pin))
#define IO_REG_TYPE uint8_t
#define IO_REG_BASE_ATTR
#define IO_REG_MASK_ATTR
#define DIRECT_READ(base, mask) ((*((base)+16) & (mask)) ? 1 : 0)
#define DIRECT_MODE_INPUT(base, mask) (*((base)+20) &= ~(mask))
#define DIRECT_MODE_OUTPUT(base, mask) (*((base)+20) |= (mask))
#define DIRECT_WRITE_LOW(base, mask) (*((base)+8) = (mask))
#define DIRECT_WRITE_HIGH(base, mask) (*((base)+4) = (mask))
#elif defined(__SAM3X8E__) || defined(__SAM3A8C__) || defined(__SAM3A4C__)
// Arduino 1.5.1 may have a bug in delayMicroseconds() on Arduino Due.
// http://arduino.cc/forum/index.php/topic,141030.msg1076268.html#msg1076268
// If you have trouble with OneWire on Arduino Due, please check the
// status of delayMicroseconds() before reporting a bug in OneWire!
#define PIN_TO_BASEREG(pin) (&(digitalPinToPort(pin)->PIO_PER))
#define PIN_TO_BITMASK(pin) (digitalPinToBitMask(pin))
#define IO_REG_TYPE uint32_t
#define IO_REG_BASE_ATTR
#define IO_REG_MASK_ATTR
#define DIRECT_READ(base, mask) (((*((base)+15)) & (mask)) ? 1 : 0)
#define DIRECT_MODE_INPUT(base, mask) ((*((base)+5)) = (mask))
#define DIRECT_MODE_OUTPUT(base, mask) ((*((base)+4)) = (mask))
#define DIRECT_WRITE_LOW(base, mask) ((*((base)+13)) = (mask))
#define DIRECT_WRITE_HIGH(base, mask) ((*((base)+12)) = (mask))
#ifndef PROGMEM
#define PROGMEM
#endif
#ifndef pgm_read_byte
#define pgm_read_byte(addr) (*(const uint8_t *)(addr))
#endif
#elif defined(__PIC32MX__)
#define PIN_TO_BASEREG(pin) (portModeRegister(digitalPinToPort(pin)))
#define PIN_TO_BITMASK(pin) (digitalPinToBitMask(pin))
#define IO_REG_TYPE uint32_t
#define IO_REG_BASE_ATTR
#define IO_REG_MASK_ATTR
#define DIRECT_READ(base, mask) (((*(base+4)) & (mask)) ? 1 : 0) //PORTX + 0x10
#define DIRECT_MODE_INPUT(base, mask) ((*(base+2)) = (mask)) //TRISXSET + 0x08
#define DIRECT_MODE_OUTPUT(base, mask) ((*(base+1)) = (mask)) //TRISXCLR + 0x04
#define DIRECT_WRITE_LOW(base, mask) ((*(base+8+1)) = (mask)) //LATXCLR + 0x24
#define DIRECT_WRITE_HIGH(base, mask) ((*(base+8+2)) = (mask)) //LATXSET + 0x28
#elif defined(ARDUINO_ARCH_ESP8266)
// Special note: I depend on the ESP community to maintain these definitions and
// submit good pull requests. I can not answer any ESP questions or help you
// resolve any problems related to ESP chips. Please do not contact me and please
// DO NOT CREATE GITHUB ISSUES for ESP support. All ESP questions must be asked
// on ESP community forums.
#define PIN_TO_BASEREG(pin) ((volatile uint32_t*) GPO)
#define PIN_TO_BITMASK(pin) (1 << pin)
#define IO_REG_TYPE uint32_t
#define IO_REG_BASE_ATTR
#define IO_REG_MASK_ATTR
#define DIRECT_READ(base, mask) ((GPI & (mask)) ? 1 : 0) //GPIO_IN_ADDRESS
#define DIRECT_MODE_INPUT(base, mask) (GPE &= ~(mask)) //GPIO_ENABLE_W1TC_ADDRESS
#define DIRECT_MODE_OUTPUT(base, mask) (GPE |= (mask)) //GPIO_ENABLE_W1TS_ADDRESS
#define DIRECT_WRITE_LOW(base, mask) (GPOC = (mask)) //GPIO_OUT_W1TC_ADDRESS
#define DIRECT_WRITE_HIGH(base, mask) (GPOS = (mask)) //GPIO_OUT_W1TS_ADDRESS
#elif defined(ARDUINO_ARCH_ESP32)
#include <driver/rtc_io.h>
#define PIN_TO_BASEREG(pin) (0)
#define PIN_TO_BITMASK(pin) (pin)
#define IO_REG_TYPE uint32_t
#define IO_REG_BASE_ATTR
#define IO_REG_MASK_ATTR
static inline __attribute__((always_inline))
IO_REG_TYPE directRead(IO_REG_TYPE pin)
{
#if CONFIG_IDF_TARGET_ESP32C3
return (GPIO.in.val >> pin) & 0x1;
#else // plain ESP32
if ( pin < 32 )
return (GPIO.in >> pin) & 0x1;
else if ( pin < 46 )
return (GPIO.in1.val >> (pin - 32)) & 0x1;
#endif
return 0;
}
static inline __attribute__((always_inline))
void directWriteLow(IO_REG_TYPE pin)
{
#if CONFIG_IDF_TARGET_ESP32C3
GPIO.out_w1tc.val = ((uint32_t)1 << pin);
#else // plain ESP32
if ( pin < 32 )
GPIO.out_w1tc = ((uint32_t)1 << pin);
else if ( pin < 46 )
GPIO.out1_w1tc.val = ((uint32_t)1 << (pin - 32));
#endif
}
static inline __attribute__((always_inline))
void directWriteHigh(IO_REG_TYPE pin)
{
#if CONFIG_IDF_TARGET_ESP32C3
GPIO.out_w1ts.val = ((uint32_t)1 << pin);
#else // plain ESP32
if ( pin < 32 )
GPIO.out_w1ts = ((uint32_t)1 << pin);
else if ( pin < 46 )
GPIO.out1_w1ts.val = ((uint32_t)1 << (pin - 32));
#endif
}
static inline __attribute__((always_inline))
void directModeInput(IO_REG_TYPE pin)
{
#if CONFIG_IDF_TARGET_ESP32C3
GPIO.enable_w1tc.val = ((uint32_t)1 << (pin));
#else
if ( digitalPinIsValid(pin) )
{
#if ESP_IDF_VERSION_MAJOR < 4 // IDF 3.x ESP32/PICO-D4
uint32_t rtc_reg(rtc_gpio_desc[pin].reg);
if ( rtc_reg ) // RTC pins PULL settings
{
ESP_REG(rtc_reg) = ESP_REG(rtc_reg) & ~(rtc_gpio_desc[pin].mux);
ESP_REG(rtc_reg) = ESP_REG(rtc_reg) & ~(rtc_gpio_desc[pin].pullup | rtc_gpio_desc[pin].pulldown);
}
//#elif ESP_IDF_VERSION_MAJOR > 3 // ESP32-S2 needs IDF 4.2 or later
// int8_t rtc_io = esp32_gpioMux[pin].rtc;
// uint32_t rtc_reg = (rtc_io != -1)?rtc_io_desc[rtc_io].reg:0;
// if ( rtc_reg ) // RTC pins PULL settings
// {
// ESP_REG(rtc_reg) = ESP_REG(rtc_reg) & ~(rtc_io_desc[rtc_io].mux);
// ESP_REG(rtc_reg) = ESP_REG(rtc_reg) & ~(rtc_io_desc[rtc_io].pullup | rtc_io_desc[rtc_io].pulldown);
// }
#endif
// Input
if ( pin < 32 )
GPIO.enable_w1tc = ((uint32_t)1 << pin);
else
GPIO.enable1_w1tc.val = ((uint32_t)1 << (pin - 32));
// uint32_t pinFunction((uint32_t)2 << FUN_DRV_S); // what are the drivers?
// pinFunction |= FUN_IE; // input enable but required for output as well?
// pinFunction |= ((uint32_t)PIN_FUNC_GPIO << MCU_SEL_S);
// ESP_REG(DR_REG_IO_MUX_BASE + esp32_gpioMux[pin].reg) = pinFunction;
// GPIO.pin[pin].val = 0;
}
#endif
}
static inline __attribute__((always_inline))
void directModeOutput(IO_REG_TYPE pin)
{
#if CONFIG_IDF_TARGET_ESP32C3
GPIO.enable_w1ts.val = ((uint32_t)1 << (pin));
#else
if ( digitalPinIsValid(pin) && pin <= 33 ) // pins above 33 can be only inputs
{
#if ESP_IDF_VERSION_MAJOR < 4 // IDF 3.x ESP32/PICO-D4
uint32_t rtc_reg(rtc_gpio_desc[pin].reg);
if ( rtc_reg ) // RTC pins PULL settings
{
ESP_REG(rtc_reg) = ESP_REG(rtc_reg) & ~(rtc_gpio_desc[pin].mux);
ESP_REG(rtc_reg) = ESP_REG(rtc_reg) & ~(rtc_gpio_desc[pin].pullup | rtc_gpio_desc[pin].pulldown);
}
//#elif ESP_IDF_VERSION_MAJOR > 3 // ESP32-S2 needs IDF 4.2 or later
// int8_t rtc_io = esp32_gpioMux[pin].rtc;
// uint32_t rtc_reg = (rtc_io != -1)?rtc_io_desc[rtc_io].reg:0;
// if ( rtc_reg ) // RTC pins PULL settings
// {
// ESP_REG(rtc_reg) = ESP_REG(rtc_reg) & ~(rtc_io_desc[rtc_io].mux);
// ESP_REG(rtc_reg) = ESP_REG(rtc_reg) & ~(rtc_io_desc[rtc_io].pullup | rtc_io_desc[rtc_io].pulldown);
// }
#endif
// Output
if ( pin < 32 )
GPIO.enable_w1ts = ((uint32_t)1 << pin);
else // already validated to pins <= 33
GPIO.enable1_w1ts.val = ((uint32_t)1 << (pin - 32));
// uint32_t pinFunction((uint32_t)2 << FUN_DRV_S); // what are the drivers?
// pinFunction |= FUN_IE; // input enable but required for output as well?
// pinFunction |= ((uint32_t)PIN_FUNC_GPIO << MCU_SEL_S);
// ESP_REG(DR_REG_IO_MUX_BASE + esp32_gpioMux[pin].reg) = pinFunction;
// GPIO.pin[pin].val = 0;
}
#endif
}
#define DIRECT_READ(base, pin) directRead(pin)
#define DIRECT_WRITE_LOW(base, pin) directWriteLow(pin)
#define DIRECT_WRITE_HIGH(base, pin) directWriteHigh(pin)
#define DIRECT_MODE_INPUT(base, pin) directModeInput(pin)
#define DIRECT_MODE_OUTPUT(base, pin) directModeOutput(pin)
//#warning "ESP32 OneWire testing"
#elif defined(__SAMD21G18A__)
#define PIN_TO_BASEREG(pin) portModeRegister(digitalPinToPort(pin))
#define PIN_TO_BITMASK(pin) (digitalPinToBitMask(pin))
#define IO_REG_TYPE uint32_t
#define IO_REG_BASE_ATTR
#define IO_REG_MASK_ATTR
#define DIRECT_READ(base, mask) (((*((base)+8)) & (mask)) ? 1 : 0)
#define DIRECT_MODE_INPUT(base, mask) ((*((base)+1)) = (mask))
#define DIRECT_MODE_OUTPUT(base, mask) ((*((base)+2)) = (mask))
#define DIRECT_WRITE_LOW(base, mask) ((*((base)+5)) = (mask))
#define DIRECT_WRITE_HIGH(base, mask) ((*((base)+6)) = (mask))
#elif defined(RBL_NRF51822)
#define PIN_TO_BASEREG(pin) (0)
#define PIN_TO_BITMASK(pin) (pin)
#define IO_REG_TYPE uint32_t
#define IO_REG_BASE_ATTR
#define IO_REG_MASK_ATTR
#define DIRECT_READ(base, pin) nrf_gpio_pin_read(pin)
#define DIRECT_WRITE_LOW(base, pin) nrf_gpio_pin_clear(pin)
#define DIRECT_WRITE_HIGH(base, pin) nrf_gpio_pin_set(pin)
#define DIRECT_MODE_INPUT(base, pin) nrf_gpio_cfg_input(pin, NRF_GPIO_PIN_NOPULL)
#define DIRECT_MODE_OUTPUT(base, pin) nrf_gpio_cfg_output(pin)
#elif defined(__arc__) /* Arduino101/Genuino101 specifics */
#include "scss_registers.h"
#include "portable.h"
#include "avr/pgmspace.h"
#define GPIO_ID(pin) (g_APinDescription[pin].ulGPIOId)
#define GPIO_TYPE(pin) (g_APinDescription[pin].ulGPIOType)
#define GPIO_BASE(pin) (g_APinDescription[pin].ulGPIOBase)
#define DIR_OFFSET_SS 0x01
#define DIR_OFFSET_SOC 0x04
#define EXT_PORT_OFFSET_SS 0x0A
#define EXT_PORT_OFFSET_SOC 0x50
/* GPIO registers base address */
#define PIN_TO_BASEREG(pin) ((volatile uint32_t *)g_APinDescription[pin].ulGPIOBase)
#define PIN_TO_BITMASK(pin) pin
#define IO_REG_TYPE uint32_t
#define IO_REG_BASE_ATTR
#define IO_REG_MASK_ATTR
static inline __attribute__((always_inline))
IO_REG_TYPE directRead(volatile IO_REG_TYPE *base, IO_REG_TYPE pin)
{
IO_REG_TYPE ret;
if (SS_GPIO == GPIO_TYPE(pin)) {
ret = READ_ARC_REG(((IO_REG_TYPE)base + EXT_PORT_OFFSET_SS));
} else {
ret = MMIO_REG_VAL_FROM_BASE((IO_REG_TYPE)base, EXT_PORT_OFFSET_SOC);
}
return ((ret >> GPIO_ID(pin)) & 0x01);
}
static inline __attribute__((always_inline))
void directModeInput(volatile IO_REG_TYPE *base, IO_REG_TYPE pin)
{
if (SS_GPIO == GPIO_TYPE(pin)) {
WRITE_ARC_REG(READ_ARC_REG((((IO_REG_TYPE)base) + DIR_OFFSET_SS)) & ~(0x01 << GPIO_ID(pin)),
((IO_REG_TYPE)(base) + DIR_OFFSET_SS));
} else {
MMIO_REG_VAL_FROM_BASE((IO_REG_TYPE)base, DIR_OFFSET_SOC) &= ~(0x01 << GPIO_ID(pin));
}
}
static inline __attribute__((always_inline))
void directModeOutput(volatile IO_REG_TYPE *base, IO_REG_TYPE pin)
{
if (SS_GPIO == GPIO_TYPE(pin)) {
WRITE_ARC_REG(READ_ARC_REG(((IO_REG_TYPE)(base) + DIR_OFFSET_SS)) | (0x01 << GPIO_ID(pin)),
((IO_REG_TYPE)(base) + DIR_OFFSET_SS));
} else {
MMIO_REG_VAL_FROM_BASE((IO_REG_TYPE)base, DIR_OFFSET_SOC) |= (0x01 << GPIO_ID(pin));
}
}
static inline __attribute__((always_inline))
void directWriteLow(volatile IO_REG_TYPE *base, IO_REG_TYPE pin)
{
if (SS_GPIO == GPIO_TYPE(pin)) {
WRITE_ARC_REG(READ_ARC_REG(base) & ~(0x01 << GPIO_ID(pin)), base);
} else {
MMIO_REG_VAL(base) &= ~(0x01 << GPIO_ID(pin));
}
}
static inline __attribute__((always_inline))
void directWriteHigh(volatile IO_REG_TYPE *base, IO_REG_TYPE pin)
{
if (SS_GPIO == GPIO_TYPE(pin)) {
WRITE_ARC_REG(READ_ARC_REG(base) | (0x01 << GPIO_ID(pin)), base);
} else {
MMIO_REG_VAL(base) |= (0x01 << GPIO_ID(pin));
}
}
#define DIRECT_READ(base, pin) directRead(base, pin)
#define DIRECT_MODE_INPUT(base, pin) directModeInput(base, pin)
#define DIRECT_MODE_OUTPUT(base, pin) directModeOutput(base, pin)
#define DIRECT_WRITE_LOW(base, pin) directWriteLow(base, pin)
#define DIRECT_WRITE_HIGH(base, pin) directWriteHigh(base, pin)
#elif defined(__riscv)
/*
* Tested on highfive1
*
* Stable results are achieved operating in the
* two high speed modes of the highfive1. It
* seems to be less reliable in slow mode.
*/
#define PIN_TO_BASEREG(pin) (0)
#define PIN_TO_BITMASK(pin) digitalPinToBitMask(pin)
#define IO_REG_TYPE uint32_t
#define IO_REG_BASE_ATTR
#define IO_REG_MASK_ATTR
static inline __attribute__((always_inline))
IO_REG_TYPE directRead(IO_REG_TYPE mask)
{
return ((GPIO_REG(GPIO_INPUT_VAL) & mask) != 0) ? 1 : 0;
}
static inline __attribute__((always_inline))
void directModeInput(IO_REG_TYPE mask)
{
GPIO_REG(GPIO_OUTPUT_XOR) &= ~mask;
GPIO_REG(GPIO_IOF_EN) &= ~mask;
GPIO_REG(GPIO_INPUT_EN) |= mask;
GPIO_REG(GPIO_OUTPUT_EN) &= ~mask;
}
static inline __attribute__((always_inline))
void directModeOutput(IO_REG_TYPE mask)
{
GPIO_REG(GPIO_OUTPUT_XOR) &= ~mask;
GPIO_REG(GPIO_IOF_EN) &= ~mask;
GPIO_REG(GPIO_INPUT_EN) &= ~mask;
GPIO_REG(GPIO_OUTPUT_EN) |= mask;
}
static inline __attribute__((always_inline))
void directWriteLow(IO_REG_TYPE mask)
{
GPIO_REG(GPIO_OUTPUT_VAL) &= ~mask;
}
static inline __attribute__((always_inline))
void directWriteHigh(IO_REG_TYPE mask)
{
GPIO_REG(GPIO_OUTPUT_VAL) |= mask;
}
#define DIRECT_READ(base, mask) directRead(mask)
#define DIRECT_WRITE_LOW(base, mask) directWriteLow(mask)
#define DIRECT_WRITE_HIGH(base, mask) directWriteHigh(mask)
#define DIRECT_MODE_INPUT(base, mask) directModeInput(mask)
#define DIRECT_MODE_OUTPUT(base, mask) directModeOutput(mask)
#else
#define PIN_TO_BASEREG(pin) (0)
#define PIN_TO_BITMASK(pin) (pin)
#define IO_REG_TYPE unsigned int
#define IO_REG_BASE_ATTR
#define IO_REG_MASK_ATTR
#define DIRECT_READ(base, pin) digitalRead(pin)
#define DIRECT_WRITE_LOW(base, pin) digitalWrite(pin, LOW)
#define DIRECT_WRITE_HIGH(base, pin) digitalWrite(pin, HIGH)
#define DIRECT_MODE_INPUT(base, pin) pinMode(pin,INPUT)
#define DIRECT_MODE_OUTPUT(base, pin) pinMode(pin,OUTPUT)
#warning "OneWire. Fallback mode. Using API calls for pinMode,digitalRead and digitalWrite. Operation of this library is not guaranteed on this architecture."
#endif
class OneWire
{
private:
IO_REG_TYPE bitmask;
volatile IO_REG_TYPE *baseReg;
#if ONEWIRE_SEARCH
// global search state
unsigned char ROM_NO[8];
uint8_t LastDiscrepancy;
uint8_t LastFamilyDiscrepancy;
uint8_t LastDeviceFlag;
#endif
public:
OneWire( uint8_t pin);
// Perform a 1-Wire reset cycle. Returns 1 if a device responds
// with a presence pulse. Returns 0 if there is no device or the
// bus is shorted or otherwise held low for more than 250uS
uint8_t reset(void);
// Issue a 1-Wire rom select command, you do the reset first.
void select(const uint8_t rom[8]);
// Issue a 1-Wire rom skip command, to address all on bus.
void skip(void);
// Write a byte. If 'power' is one then the wire is held high at
// the end for parasitically powered devices. You are responsible
// for eventually depowering it by calling depower() or doing
// another read or write.
void write(uint8_t v, uint8_t power = 0);
void write_bytes(const uint8_t *buf, uint16_t count, bool power = 0);
// Read a byte.
uint8_t read(void);
void read_bytes(uint8_t *buf, uint16_t count);
// Write a bit. The bus is always left powered at the end, see
// note in write() about that.
void write_bit(uint8_t v);
// Read a bit.
uint8_t read_bit(void);
// Stop forcing power onto the bus. You only need to do this if
// you used the 'power' flag to write() or used a write_bit() call
// and aren't about to do another read or write. You would rather
// not leave this powered if you don't have to, just in case
// someone shorts your bus.
void depower(void);
#if ONEWIRE_SEARCH
// Clear the search state so that if will start from the beginning again.
void reset_search();
// Setup the search to find the device type 'family_code' on the next call
// to search(*newAddr) if it is present.
void target_search(uint8_t family_code);
// Look for the next device. Returns 1 if a new address has been
// returned. A zero might mean that the bus is shorted, there are
// no devices, or you have already retrieved all of them. It
// might be a good idea to check the CRC to make sure you didn't
// get garbage. The order is deterministic. You will always get
// the same devices in the same order.
uint8_t search(uint8_t *newAddr, bool search_mode = true);
#endif
#if ONEWIRE_CRC
// Compute a Dallas Semiconductor 8 bit CRC, these are used in the
// ROM and scratchpad registers.
static uint8_t crc8(const uint8_t *addr, uint8_t len);
#if ONEWIRE_CRC16
// Compute the 1-Wire CRC16 and compare it against the received CRC.
// Example usage (reading a DS2408):
// // Put everything in a buffer so we can compute the CRC easily.
// uint8_t buf[13];
// buf[0] = 0xF0; // Read PIO Registers
// buf[1] = 0x88; // LSB address
// buf[2] = 0x00; // MSB address
// WriteBytes(net, buf, 3); // Write 3 cmd bytes
// ReadBytes(net, buf+3, 10); // Read 6 data bytes, 2 0xFF, 2 CRC16
// if (!CheckCRC16(buf, 11, &buf[11])) {
// // Handle error.
// }
//
// @param input - Array of bytes to checksum.
// @param len - How many bytes to use.
// @param inverted_crc - The two CRC16 bytes in the received data.
// This should just point into the received data,
// *not* at a 16-bit integer.
// @param crc - The crc starting value (optional)
// @return True, iff the CRC matches.
static bool check_crc16(const uint8_t* input, uint16_t len, const uint8_t* inverted_crc, uint16_t crc = 0);
// Compute a Dallas Semiconductor 16 bit CRC. This is required to check
// the integrity of data received from many 1-Wire devices. Note that the
// CRC computed here is *not* what you'll get from the 1-Wire network,
// for two reasons:
// 1) The CRC is transmitted bitwise inverted.
// 2) Depending on the endian-ness of your processor, the binary
// representation of the two-byte return value may have a different
// byte order than the two bytes you get from 1-Wire.
// @param input - Array of bytes to checksum.
// @param len - How many bytes to use.
// @param crc - The crc starting value (optional)
// @return The CRC16, as defined by Dallas Semiconductor.
static uint16_t crc16(const uint8_t* input, uint16_t len, uint16_t crc = 0);
#endif
#endif
};
#endif
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