From 5a4ce8cc3400aab6b3d74d408161bbac46803dba Mon Sep 17 00:00:00 2001 From: MrC Date: Mon, 4 May 2026 01:49:59 +0000 Subject: [PATCH] =?UTF-8?q?Clarify=20Canjector=20naming=20=E2=80=94=20name?= =?UTF-8?q?s=20printed=20on=20boards,=20note=20functional=20overlap?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit - Start/Minor/Middle/Major/Endz are the actual PCB names - Start and Endz both serve end-of-chain - Minor and Middle both have 3 CAN ports - All use shunt-activated termination --- sources/2890/canjectors.md | 24 ++++++++++++++---------- 1 file changed, 14 insertions(+), 10 deletions(-) diff --git a/sources/2890/canjectors.md b/sources/2890/canjectors.md index 19f27bf..d4e6ada 100644 --- a/sources/2890/canjectors.md +++ b/sources/2890/canjectors.md @@ -52,19 +52,23 @@ The schematic shows the "middle" Canjector variant with: ## Design Variants -Chris designed five Canjector variants to form a complete CAN bus distribution system. All variants support configurable termination via a shunt jumper — populate the shunt to activate 120Ω termination at any position in the chain. +Chris designed five Canjector variants. **Names are printed on the physical PCBs** — Endz, Major, Minor are the actual designations. -| Variant | CAN connections | 12V outputs | Termination | Typical use | -|---------|----------------|-------------|-------------|-------------| -| **Start** | 1 | 1 | Shunt-activated | Bus origin at PDH | -| **Minor** | 3 | 1 | Shunt-activated | Intermediate node | -| **Middle** | 3 | 2 | Shunt-activated | Intermediate node + power distribution | -| **Major** | 6 | 2 | Shunt-activated | End of chain (large node) | -| **Endz** | 1 | 1 | Shunt-activated | Start OR final terminator — diagnostic USB interface | +All variants support configurable termination via a shunt jumper — populate the shunt to activate 120Ω termination anywhere in the chain. -**All Canjectors share the same termination philosophy:** no fixed termination at any position. Use a shunt jumper to enable 120Ω termination exactly where the bus physics require it. This eliminates the need for separate "terminating" and "non-terminating" variants. +| PCB Name | CAN ports | 12V outs | Primary role | +|----------|-----------|----------|-------------| +| **Start** | 1 | 1 | Bus origin at PDH side | +| **Minor** | 3 | 1 | Mid-chain node | +| **Middle** | 3 | 2 | Mid-chain node + power distribution | +| **Major** | 6 | 2 | Heavy distribution — end of main runs | +| **Endz** | 1 | 1 | USB diagnostic tap — serves as first OR last device in chain | -**Endz** is unique — it's the diagnostic variant with a USB Type-B connector for direct laptop-to-CAN connection. Meant to serve as either the first or last device in the chain. Currently experiencing design problems; no working units on hand. +**Note on overlap:** +- Start and Endz both serve end-of-chain positions (first or last device) +- Minor and Middle both have 3 CAN ports — Middle adds a second 12V output for power distribution + +All Canjectors use the same shunt-activation scheme for 120Ω termination. This means any variant can terminate the bus when needed. ## Connection to Training