Table of contents
  1. BSD Card Quickstart
    1. Overview
    2. Quickstart Checklist
    3. What You Need
    4. Step 1 – Install the Node Card and BSD Card
    5. Step 2 — Connect the BSD Card to the Block Breakout Board
    6. Step 3 — Configure the BSD Card
    7. Step 4 — Test and Verification
      1. Occupancy Detection
      2. Short Detection
    8. Related Documentation

BSD Card Quickstart

Overview

This Quickstart walks you through:

  1. installing the BSD Card and its Block Breakout Board
  2. wiring a single gapped block
  3. applying layout power
  4. validating the end-to-end event path, confirming that block-detection signals from the BSD Card appear as the expected Occupied/Clear LCC events on the CAN bus

The diagram below shows the flow of detection and communication through the system:

Track → Block Breakout Board → BSD Card → Node Bus Hub → Node Card → CAN Bus


Quickstart Checklist

Do these steps in order:

  1. Insert Cards
    • Install an ESP32-S2 DevKit-C Module with installed firmware onto the BSD Card
    • Install the Node Card and BSD Card into a Node Bus Hub.
    • Power the Node Card.
  2. Connect to the Breakout Board
    • Set the BSD Card’s COMM BUS (A/B) and COMM ADDR (1–7).
    • Connect the BSD Card’s J1 or J2 to the Breakout Board’s BSD/BSD CARDS port.
    • Optionally install a SSD1306/1309 LCD Display (J3)
  3. Wire Track and Blocks
    • Connect gapped Rail B for Blocks 1–4 to TRACK BLOCKS – GAPPED RAIL B (J1).
    • Connect layout Track Bus B to TRACK BUS B (J2).
    • If both rails are gapped:
      • Set JP1–JP4 jumpers
      • Connect layout Track Bus A to TRACK BUS A (J2).
  4. Configure CDI
    • Match CDI COMM Bus + COMM Addr to the card’s switches.
    • Fill in Card Description and Block Descriptions.
    • Adjust Debounce only if needed.
    • Set the Initial Power-On State.
  5. Verify Detection
    • Place a locomotive or resistor wheelset on the block.
    • Confirm: LED → Occupied Event → Clear Event after removal.

What You Need


Step 1 – Install the Node Card and BSD Card

  1. Install a tested Node Card into a test Node Bus Hub.
  2. Install the ESP32 Module into a tested BSD Card
  3. Install the tested BSD Card into the same Node Bus Hub.
  4. Power the Node Card.

Step 2 — Connect the BSD Card to the Block Breakout Board

  1. On the BSD Card
    1. Configure communications to a unique setting across cards:
      • Set the COMM BUS to either Bus A or Bus B (JP1/JP2).
      • Set the COMM ADDR to 1 through 7 by sliding the switches (SW1)
    2. Connect a network cable to BLOCK BREAKOUT BOARD BLOCKS 1–4 (J1)
  2. On the Block Breakout Board
    1. Ensure the layout track bus is powered off.
    2. Connect the other end of the network cable to the BSD/BSD CARDS connector (J2).
      • This carries the gapped Rail B detection current to/from the BSD Card.
    3. If any of the blocks are at the end of the track bus, set the DCC BUS SNUBBER using a jumper.
    4. If a block has both rails gapped, then:
      1. Set the corresponding JP1–JP4 jumper(s) to enable that block’s current detection, and
      2. Connect TRACK BUS A (J2) to the layout’s Track Bus A.

Step 3 — Configure the BSD Card

  1. Open the CDI Configuration Tool.
  2. Locate the appropriate LCC Node.
  3. Open the BSD Card segment.

  4. Update the Card Description field
    • Use a meaningful name that tells you what this card is watching, for example:
      • Mainline Zone 54 Blocks
      • Staging Yard A Blocks
    • This makes it much easier to identify the card later when you have multiple BSD Cards on the layout.
  5. Update each Block / Line Description
    • For each block input on the card, fill in a short description that ties it back to the layout, for example:
      • Zone 54, Block 1
      • Zone 54, Block 2 (East Siding)
    • Use a consistent naming pattern so wiring, CDI, and documentation all line up.
  6. Set the valid range for Occupancy, where currecnt levels
    • below the range result in detection
    • above the range result in a short event and circuit being disconnected
  7. Set the Debounce value
    • Start with the default debounce time.
    • If testing shows noisy occupancy (flicker, rapid changes), increase the debounce value slightly.
    • If detection feels too sluggish, you can reduce it—but only after confirming the track and wiring are clean.
  8. Set the Initial Power-On State
    • Choose how each block should report when the layout first powers up:
      • Some operations prefer all blocks to come up as Clear until detection says otherwise.
      • Others may want a more conservative behavior, depending on operating practices and safety preferences.
    • Actual operations on your layout will determine the best choice here.
  9. Use the default event IDs unless you have a specific event mapping strategy in place.

Step 4 — Test and Verification

Occupancy Detection

Place a locomotive or resistor wheelset on your test block.

Expected behavior:

Remove the locomotive or resistor wheelset.

Expected behavior:


Short Detection

Short the track

Expected behavior:

Remove the short

Expected behavior:

This confirms the complete detection / short chain: Track → Block Breakout Board → BSD Card → CAN → Node Card → CDI