Castle Serial Link ESC telemetry to FrSky Smartport

Send Castle Serial Link ESC telemetry to Frsky Smartport using an Arduino Pro Mini 168 or 328P (3.3v or 5v)

ESC telemetry

Interfacing the ESC with Castle Serial Link it is possible to send the telemetry to Smartport protocol using an Arduino

Telemetry sensors (sensor ID: 10):

• Voltage: sensor EscV (0x0B50)
• Ripple voltage: sensor EscV (0x0B52)
• Current: sensor EscA (0x0B50)
• RPM: sensor EscR (0x0B60)
• BEC voltage: sensor EscV (0x0B51) or BecV (0x0E50)
• BEC current: sensor EscA (0x0B51) or BecA (0x0E50)
• Temperature: sensor EscT (0x0B70)
• Temperature NTC: sensor EscT (0x0B71)

Note: my ESC (ICE2HV80) does not output bec and current telemetry
Note2: some sensors have custom names. This has to be done manually from edit sensor screen in openTx

Wiring:

• SmartPort Vcc to Arduino RAW
• SmartPort Gnd to Arduino Gnd
• Smartport Signal to Arduino PIN_SMARTPORT_RX (7)
• Smartport Signal to R1 (4.7k)
• R1 (4.7k) to Arduino PIN_SMARTPORT_TX (12)
• Castle Serial Link Rx to Arduino Tx
• Castle Serial Link Tx to Arduino Rx

Adjust RPM sensor value

• Blades/poles: number of pair of poles * main gear teeth
• Multiplies: pinion gear teeth

Flash to Arduino

Using Arduino IDE copy folder castle_telemetry and open castle_telemetry.ino. Select board Arduino Pro or Pro Mini, processor ATMega168 or ATMega328P (3.3V 8MHz or 5V 16MHz) and flash