CAN Bus Pinout for RJ-11 (Phone) Jacks

[Hugh Vartanian]

Hi,
I'm looking for a physical layer spec for using a modular jacks on the
CAN bus in my system. Right now I have 9 pin 'D' jacks per the CIA
Standard 102 Version 2.0. Looking to save some board space and cable
expense.

Also, any thoughts on the reserved signals? I'm using one of them as a
wired-or safety power release (logic level). If anything (interlock
switches, a processor which detects a jam, etc.) pulls it to ground a
power relay on each board releases the electromechanical power in my
system....

hugh.va...@cytyc.com

Thanks a bunch.

[Olaf 'Olu' Pfeiffer]

Hugh Vartanian wrote:
> I'm looking for a physical layer spec for using a modular jacks on the
> CAN bus in my system. Right now I have 9 pin 'D' jacks per the CIA
> Standard 102 Version 2.0. Looking to save some board space and cable
> expense.

Just the other day I saw a CAN application using telephone
jacks and cables. 2 jacks on each hardware.

Olaf 'Olu' Pfeiffer
http://www.hitex.com [/olu]

[Zanthic Technologies Inc.]

Hugh Vartanian wrote:
>
> Hi,

> I'm looking for a physical layer spec for using a modular jacks on the
> CAN bus in my system. Right now I have 9 pin 'D' jacks per the CIA
> Standard 102 Version 2.0. Looking to save some board space and cable
> expense.
>

> Also, any thoughts on the reserved signals? I'm using one of them as a
> wired-or safety power release (logic level). If anything (interlock
> switches, a processor which detects a jam, etc.) pulls it to ground a
> power relay on each board releases the electromechanical power in my
> system....
>
> hugh.va...@cytyc.com
>
> Thanks a bunch.

We use 8 wire RJ-45 sockets for our products. Each board has two sockets
to allow easy daisy chaining of boards. The end two have RJ-45 plugs
with the termination resistor crimped in. Although there are 8 wires
we are currently only using 5. Standard catagory-5 computer network cables
can be purchased for a few dollars each and save alot of work making up
cables. Our industrial customers usually wire up their own external
connections directly off a header.

Our RJ-45 wiring is used within our systems and does not claim any
alliance with any other manufacture, but your welcome to use it.

Pin 1 Not connected
Pin 2 DC supply (usually 12 volts but can be 9 to 24v)
Pin 3 Ground
Pin 4 CAN bus low
Pin 5 CAN bus high
Pin 6 Not connected
pin 7 Cable Reset
Pin 8 not connected

pin 1 is defined as the left hand pin when looking INTO the socket with the
wires on the top and the key lock on the bottom.

Cable reset is a line that can be pulled low by a PC running our monitor
program that will reset any node that has this feature enabled. This allows
the developer to do a hardware reset on a node that may not be easily
accessable.

We have used a 6 pin standard Military Style connector for a number of
our military contracts and a number of our customers have adopted the same.
A typical node would have two, 6 pin chassis mount sockets, Bendix MS3120F
with the following pinouts,

A - DC power
B - Ground
C - CAN low
D - CAN High
E - not connected or negitive voltage
F - Cable reset

As far as the safety release system, I've used the philips 82C150 SLIO CAN
device to pull in a relay when a "real" CAN node activates it. It has a
nice feature in that if the CAN messages are not constantly updated (around
50mS) the SLIO resets all outputs to floating. The relay controls
the main power to the machine and if the main processor fails, the program
fails, or the CAN bus fails, the relay releases within 50mS.

Hope this helps,

Steve Letkeman

BTW, I have pictures of a experimental remotely controlled electric vehicle
CAN controlled (of course) on my web page if anyone is interested.
--
Zanthic Technologies Inc.
http://www.zanthic.com/public/zanthic
68HC11/CAN (Controller Area Network) Development Systems.

[Jarmo Alanen]

Zanthic Technologies Inc. wrote:
>
>
> We use 8 wire RJ-45 sockets for our products.

The M3S specification (CAN specification for wheelchairs etc.) uses also
RJ-45 connector.
See http://www.tno.nl/m3s/ -> Specification.

The pinning is:

Pin 1 KEY_L ('power on/off' signal for the modules)
Pin 2 BATTERY_M (minus 0 V)
Pin 3 CAN_H (high)
Pin 4 CAN_L (low)
Pin 5 BATTERY_P (plus 24 V)
Pin 6 BATTERY_M (minus 0 V)
pin 7 BATTERY_M (minus 0 V)
Pin 8 DMS_L ('dead man switch' signal)

===========================================
Jarmo Alanen
VTT AUTOMATION, Machine Automation
P.O.Box 13021, FIN 33101 TAMPERE, Finland
tel. +358 3 316 3602, fax +358 3 316 3494
e-mail: Jarmo....@vtt.fi, Web: http://www.vtt.fi/aut/kau
===========================================