Cansat
/
DShotRMT
2
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

...cleaning 

...experimental DSHOT1200 support. Who really needs DSHOT1200???
This commit is contained in:
Wastl Kraus 2025-06-13 13:50:10 +02:00
parent 64fd2edfba
commit 84adfe026a
3 changed files with 47 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

28
DShotRMT.cpp
View File

@ -19,8 +19,8 @@ void DShotRMT::begin()
{
rmt_rx_channel_config_t rmt_rx_channel_config = {
.gpio_num = _gpio,
.clk_src = RMT_CLK_SRC_DEFAULT,
.resolution_hz = DEFAULT_RES_HZ,
.clk_src = DSHOT_CLOCK_SRC_DEFAULT,
.resolution_hz = DSHOT_RMT_RESOLUTION,
.mem_block_symbols = 64,
.flags = {
.invert_in = false,
@ -32,8 +32,8 @@ void DShotRMT::begin()
rmt_tx_channel_config_t rmt_tx_channel_config = {
.gpio_num = _gpio,
.clk_src = RMT_CLK_SRC_DEFAULT,
.resolution_hz = DEFAULT_RES_HZ,
.clk_src = DSHOT_CLOCK_SRC_DEFAULT,
.resolution_hz = DSHOT_RMT_RESOLUTION,
.mem_block_symbols = 64,
.trans_queue_depth = 1,
.flags = {
@ -88,11 +88,10 @@ void DShotRMT::setThrottle(uint16_t throttle)
dshot_packet = (dshot_packet << 4) | crc;
// Encode DShot Paket
rmt_symbol_word_t symbols[32] = {};
rmt_symbol_word_t symbols[DSHOT_BITS_PER_FRAME] = {}; // 16 DShot Bits + Pause Bit
size_t count = 0;
buildFrameSymbols(dshot_packet, symbols, count);
// Reset RMT Signnal loop before sending new value
rmt_disable(_rmt_tx_channel);
rmt_enable(_rmt_tx_channel);
@ -104,12 +103,21 @@ void DShotRMT::setThrottle(uint16_t throttle)
//
void DShotRMT::buildFrameSymbols(uint16_t dshot_packet, rmt_symbol_word_t *symbols, size_t &count)
{
// Always start from the top
count = 0;
//
uint32_t ticks_per_bit = 0;
uint32_t ticks_zero_high = 0;
uint32_t ticks_one_high = 0;
switch (_mode)
{
case DSHOT_OFF:
ticks_per_bit = 0;
ticks_zero_high = 0;
ticks_one_high = 0;
break;
case DSHOT150:
ticks_per_bit = 64;
ticks_zero_high = 24;
@ -125,11 +133,18 @@ void DShotRMT::buildFrameSymbols(uint16_t dshot_packet, rmt_symbol_word_t *symbo
ticks_zero_high = 6;
ticks_one_high = 12;
break;
case DSHOT1200:
ticks_per_bit = 8;
ticks_zero_high = 3;
ticks_one_high = 6;
break;
}
//
uint32_t ticks_zero_low = ticks_per_bit - ticks_zero_high;
uint32_t ticks_one_low = ticks_per_bit - ticks_one_high;
// Fill the 16 DShot-Bits Array with selected timings
for (int i = 15; i >= 0; i--)
{
bool bit = (dshot_packet >> i) & 0x01;
@ -140,6 +155,7 @@ void DShotRMT::buildFrameSymbols(uint16_t dshot_packet, rmt_symbol_word_t *symbo
count++;
}
// Append the Pause Bits
symbols[count].level0 = 0;
symbols[count].duration0 = ticks_per_bit * PAUSE_BITS;
symbols[count].level1 = 0;

15
DShotRMT.h
View File

@ -12,20 +12,29 @@
#include <driver/rmt_tx.h>
#include <driver/rmt_rx.h>
// DShot Protocol Constants
static constexpr auto DSHOT_THROTTLE_FAILSAVE = 0;
static constexpr auto DSHOT_THROTTLE_MIN = 48;
static constexpr auto DSHOT_THROTTLE_MAX = 2047;
static constexpr auto DEFAULT_RES_HZ = 10 * 1000 * 1000; // 10 MHz
static constexpr auto DSHOT_BITS_PER_FRAME = 17;
static constexpr auto PAUSE_BITS = 21;
static constexpr auto DSHOT_NULL_PACKET = 0b0000000000000000;
static constexpr auto DSHOT_FULL_PACKET = 0b1111111111111111;
static constexpr auto NO_ERPM_SIGNAL = 0;
static constexpr auto DSHOT_CLOCK_SRC_DEFAULT = RMT_CLK_SRC_DEFAULT;
static constexpr auto DSHOT_RMT_RESOLUTION = 10 * 1000 * 1000; // set 10 MHz RMT Resolution
// DShot Mode Selection
typedef enum dshot_mode_e
{
DSHOT_OFF,
DSHOT150,
DSHOT300,
DSHOT600
DSHOT600,
DSHOT1200
} dshot_mode_t;
//
class DShotRMT
{
public:
@ -41,7 +50,7 @@ private:
gpio_num_t _gpio;
dshot_mode_t _mode;
bool _isBidirectional;
uint16_t _lastThrottle = 0;
uint16_t _lastThrottle = DSHOT_FULL_PACKET;
uint16_t dshot_packet = DSHOT_NULL_PACKET;
rmt_channel_handle_t _rmt_tx_channel = nullptr;

14
examples/dshot300/dshot300.ino
View File

@ -17,7 +17,7 @@ constexpr auto USB_SERIAL_BAUD = 115200;
constexpr auto MOTOR01_PIN = GPIO_NUM_17;
constexpr auto DSHOT_MODE = DSHOT300;
// BiDirectional DShot Support
// BiDirectional DShot Support (default: false)
constexpr auto IS_BIDIRECTIONAL = true;
// Setup Motor Pin, DShot Mode and optional BiDirectional Support
@ -25,6 +25,7 @@ DShotRMT motor01(MOTOR01_PIN, DSHOT_MODE, IS_BIDIRECTIONAL);
void setup()
{
// Start the USB Serial Port
USB_Serial.begin(USB_SERIAL_BAUD);
// Initialize DShot Signal
@ -34,16 +35,23 @@ void setup()
motor01.setThrottle(DSHOT_THROTTLE_MIN);
//
USB_Serial.println("**********************");
USB_Serial.println("DShotRMT Demo started.");
USB_Serial.println("Enter a throttle value (48 – 2047):");
}
void loop()
{
// Simple as can be
// Read value input from Serial
int throttle_input = readSerialThrottle();
// Now send the value
motor01.setThrottle(throttle_input);
// BiDirectional DShot: print out the received eRPMs
if (IS_BIDIRECTIONAL)
{
}
}
// Reads throttle value from serial input
@ -63,7 +71,7 @@ int readSerialThrottle()
USB_Serial.print("Throttle set to: ");
USB_Serial.println(last_throttle);
USB_Serial.println("***********************************");
USB_Serial.println("Enter a throttle value (48 – 2047):");
}