My Homebrew D21 decoder is a double sided mobile decoder with Next18 (NEM-662) connector. The decoder is designed to integrate into the RTB digital control infrastructure.
See also
User Guides
- User Guide - DE
- User Guide - EN
- Next18 (NEM-662) connector
- DCC
- DCC-A automatic logon
- DCC-R protocol extension
- Service Mode Programming
- Railcom
- Channel 1/2
- POM, xPOM
- DYN: Speed, QoS, Track-voltage, Motor-current, AUX-current, Temp, Distance travelled
- Double sided
- Dimension: 15 x 9.5 mm
- 7-20V track voltage
- heartbeat LED
- adjustable max motor current (default 300mA)
- adjustable max AUX current (default 500mA)
- over temp protection
- Function output: LF/LR (dimmable, 1.4kHz) open drain
- Function output: AUX1/AUX2 (dimmable, 1.4kHz) open drain
- Function output: AUX3/AUX4 logic level (3.3V) or ZBCLK/ZBDAT (3.3V)
- Function output: AUX5/AUX6 logic level (3.3V)
- optional external buffer capacitor (max. 1500uF)
- <10mA idle power consumption
- SUSI3 (3.3V logic level)
- Firmware update over main tracks via DCC-R protocol
The current PCB layout uses SMD footprints with 0.5mm pitch and 0402 parts. Reflow soldering is recommended.
- 6-layer PCB, FR4, 15 x 9.5 x 0.8mm (double sided)
- CPU: AVR64DD28
- Motor bridge: DRV8231
- Connector: Next18 (NEM-662)
Filename structure: { pcb }{ code }{ version }.hex
Example: D21F0001.hex
| Description | |
|---|---|
| pcb | Name of matching hardware (D21) |
| code | Type of code contained (R=rom, B=bootloader, F=flash, U=bld update, P=UPDI factory code) |
| version | Release version (####) |
| top | bottom |
|---|---|
 |
 |
Some YouTubes to see the D21 motor driver in action.
This project is intended for hobby use only and is distributed in accordance with the Apache License 2.0 agreement.