Design Log DEC 050 encoder blade terminal refdes corrected from bt to j convention - thepinkmile/Enigma-NG GitHub Wiki

DEC-050 - Encoder Blade Terminal RefDes Corrected from BT to J Convention

  • Status: Active
  • Date: 2026-05-01
  • Category: Electrical
  • Area: Encoder Board

Decision

The 64 PCB spade blade terminals (Keystone 1285-ST) on the Encoder board have been renamed from BT1-BT64 to J3-J66.

Rationale

BT is the IPC/EDA standard reference designator prefix for batteries. Using it for PCB-mount blade/spade terminals was non-standard and created ambiguity with the Controller board's BT1 (CR2032 holder). All connectors and interface terminals in this project use the J prefix (connector/jack convention). J1 and J2 are already assigned on the Encoder board (J1 = plugboard jack sockets off-board, J2 = IDC service connector), so the blade terminal bank begins at J3.

Alternatives Considered

  • XT (external terminal) - used by some EDA conventions but J is more widely recognised and consistent with all other connector RefDes in this project.
  • Retain BT - rejected: collides with the IPC battery prefix and conflicts with BT1 on the Controller board.

Impact

  • design/Electronics/Encoder/Design_Spec.md - BOM row and ยง4 interconnects text updated.
  • design/Electronics/Encoder/Board_Layout.md - signal group table updated.
  • design/Software/CPLD_Logic/Encoder_Logic.md - all BT1-BT64 references updated.
  • design/Electronics/Consolidated_BOM.md - Encoder row RefDes updated.
  • design/Datasheets/SaiBuy_Ltd_6p35mm_Mono_Jack_Pseudo_Datasheet.md - system-level wiring notes updated; decode-half now references J3-J66 on the decode Encoder board and encode-half references J3-J66 on the encode Encoder board.