MatekSYS CRSF TO PWM-B CONVERTER

CRSF-PWM Converter, CRSF-PWM-B

• Compatible with CRSF protocol receiver only
• Support any CRSF protocol receivers (including 433MHz, 868MHz, 915MHz, 2.4GHz)
• 8x PWM outputs
• PWM frequency configurable (50Hz default, 100,160,330, 400Hz)
• 2x UARTs (for Receiver and GPS)
• Telemetry ID: RxBt, Curr, Capa, Bat%, GPS, GSpd, Hdg, Alt, Sats
• 5.5~30V battery voltage input @ Vbat pad
• BEC 5V built-in (5A continuous /6A Peak)
• Compatible with external Current sensor (0~3.3V)
• Vbat and Current sensor scale configurable
• Firmware upgradeable
• 33mm x 21mm, 4.6g
• Packing: 1x CRSF-PWM-B,  Dupont 2.54 pins

Pinouts and Pads

• Tx1/Rx1(UART1) for CRSF protocol Receiver
• Tx2/Rx2(UART2) for GPS/firmware update/setting parameters
• 1~10: CH1~CH10 PWM outputs
• Curr: current sensor signal (0~3.3V)
• Vbat(CRSF-PWM-6 and -C ): (0~36V) Battery voltage sensing
• Vbat(CRSF-PWM-B) ): (6~30V) Battery voltage sensing and power supply of onboard BEC
• G: ground
• 4v5 pad voltage = 5V pad voltage -0.3V,  make sure the voltage on 5V pad is not higher than receiver and GPS rated voltage.

Failsafe (FW 1.1.1 or older)

• Failsafe value is set automatically after CRSF-PWM board is powered on and receive CRSF signal. LED blinks 8 times quickly.
• Failsafe value = The PWM value of each channel(except CH3) when CRSF signal is received by CRSF-PWM board for the first time
• CH3 is specially arranged for the throttle,  Failsafe value = 988 by default.
• Usually put the Throttle  joystick to the lowest point,  put AIL(Roll), ELE(Pitch), RUD(Yaw) middle before powering on receiver.

Failsafe (FW 2.0.0 or newer)

• CH3 is arranged for the throttle,  Failsafe value = 988 by default.  you can change the failsafe value of CH3 and other channels by following settings.
• Make sure ESC signal is disconnected from CRSF-PWM board before starting failsafe settings
• Bridge PWM1 and PWM2 signal pad, then power on CRSF-PWM board and receiver.
• Failsafe value will be saved automatically after CRSF-PWM board is powered on and receive CRSF signal. LED blinks 8 times quickly.
• Failsafe value = The PWM value of each transmitter channel when CRSF signal is received by CRSF-PWM board.
• Remove the jumper between PWM 1 and 2,  then CRSF-PWM board will work in normal PWM output mode.

LED status

• slow blinks: CRSF-PWM board doesn’t receive CRSF signal, e.g., receiver is not bound with transmitter, receiver is not connected to UART1 of CRSF-PWM board.
• 8x quick blinks: CRSF-PWM board received CRSF signal and failsafe value is saved. (firmware 1.1.1 or older)
• solid ON:  CRSF-PWM board and receiver are working normally
• 2x slow blinks between 8x fast blink and solid on: CLI mode is active  (firmware 1.1.1 or older)

GPS telemetry

• Compatible with GPS NMEA protocol, 1Hz, Baud 9600~115200
• GPS “TX” to CRSF-PWM board “RX” Single wire half duplex UART connection,   CRSF-PWM board “TX” to GPS “RX” is not essential.
• Support GPS Telemetry ID: GPS, GSpd, Hdg, Alt, Sats
• u-blox series GPS can output “0+1 – UBX+NMEA” protocol by default
• Sensors(GPS, GSpd, Hdg, Alt, Sats) will blink in Transmitter TELEMETRY tab once CRSF-PWM board has connection with GPS.
• Troubleshooting for no GPS telemetry,  double check the wiring between GPS and CRSF-PWM board,  some u-blox GPS may don’t output NMEA protcol, you need to revert GPS to default configuration in u-center.
• with OpenTX Telemetry Logging, You can plot your flight path or search the lost plane.

VSpd telemetry (Vario)

• VSpd telemetry is supported by ExpressLRS 2.0, EDGE 2.6, OPENTX 2.2 or newer.
• support barometer MS5611(I2C address 0x77) and SPL06-001 (I2C address 0x76)

TIM & PWM Frequency

• PWM frequency on all 10x Channels can be configured according to TIM
• PWM run at 50Hz by default
• TIM2:  CH1, CH2, CH4
• TIM16: CH3
• TIM3:  CH5, CH6, CH7, CH8
• TIM1:  CH9, CH10

CLI mode

• If CRSF-PWM board doesn’t detect GPS connected to UART2 within 10 seconds after powering on,  CLI mode will active.
• After CLI mode is active, CRSF-PWM board can be connected to configurator via USB-TTL module/FC passthrough.
• in CLI mode, CRSF-PWM board firmware can be updated
• CLI mode has no effect to receiver CRSF signal and PWM outputs