Author Topic: Very high quality CAN BUS adapters at super price  (Read 3116 times)

rich.carroll

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Very high quality CAN BUS adapters at super price
« on: June 01, 2017, 11:46:19 PM »
I had occasion to pick up a pair of GridConnect CAN RS232 adapters at a cheap price a couple of months ago, while trying to interface some pieces to a CAN BUS system.  These adapters are designed to connect between a DB-9 connector (a common 9 pin serial port) and a CAN BUS system.  These are the older adapters, the newer ones connect the CAN BUS to  USB connector.  Many older devices and laptops have a serial port with a DB-9 connector, or a simple USB-DB-9 connector is easily found and quite cheap.

Today, I found two more on EBay  at http://www.ebay.com/itm/Canbus-Adapter-/332145244286?hash=item4d5566387e:g:fjgAAOSwXeJYJ5sp and there are two in the box, along with two regulated 500 milliamp power supplies, and the complete CD of manuals, currently priced at a Buy-It-Now $16.96 including shipping for two.  These sell for  $240 for the pair.  http://gridconnect.com/rs232-can-converter.html  In addition, the company is local, and extremely helpful, even though these units are older stock.  These units are new, in the original box.

This will allow you to interface your laptop (or smartphone with a USB OTG adapter) to the CANBUS in any EV made since 1996. You can send and receive commands from your laptop through one of these adapters quite easily.  But even niftier, is to add onto your CAN BUS system by connecting two of these adapters.   In order to make many these things work, you need two CAN bus connections, one to send a signal, and one to receive signals. This is two adapters in the box along with all the manuals on CD ROM for under $17.

If you plan to connect directly to the CAN BUS system, you will need to connect the two terminals on the adapter to the twisted wire pair for the CAN BUS network in the vehicle.  That twisted wire pair is easy to find, and carries CAN-High and CAN-Low signals.  If you plan to interface with the OBDII port under your dashboard, you will need to get a cable to interface with that port.  Warning, there are two cables that have a OBDII male end and a DB-9 connector, one is an interface cable and one is an adapter cable.  For the Grid Connect adapters, you need the Interface cable; I found one at Mouser http://www.mouser.com/search/ProductDetail.aspx?r=734-OBD-M-DB9-F-ES If you plant to use an arduino or a raspberry pi, you likely will use the SparkFun board at https://www.sparkfun.com/products/9555  Spark Fun sells a cable that works with their board.  What is the difference?
                 Adapter Cable - Sparkfun       Interface cable - GridConnect
OBD II             16 Pin  : DB9         16 Pin : DB9
Battery Power             16 : 9      16 : 6
Chassis Ground               4 : 1+2        4 : 3
Signal Ground             5 : 1+2          5 : 3
CAN High J-2284               6 : 3        6 : 2
CAN Low J-2284            14 : 5      14 : 7
ISO 9141-2 K Line              7 : 4         7 : 1
ISO 9141-2 L Line           15 : 8         15 : 8  (same)
J2850 BUS-               10 : 6         10 : 9
J2850 BUS+           2 : 7          2 : 5
                  ?      9 : 4
             Jayco Systems         Mouser
            
As you can see, the CAN HI, which is on Pin 6 of the OBD II connector is on Pin 3 of the DB-9 from SparkFun and Pin 2 of the DB-9 from Mouser (GridConnect compatible)

                                 CAN LO which is on Pin 14 of the OBD II connector is on Pin 5 of the DB-9 from SparkFun, and Pin 7 of the DB-9 from Mouser.

So, If you are going to use the OBDII connector under the dash as a connection point, get the correct cable and you will be fine with either the Grid Connect or the Spark Fun system.

Rich Carroll                           rc@rc.to

simon.gibson

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Re: Very high quality CAN BUS adapters at super price
« Reply #1 on: June 14, 2017, 11:49:05 AM »
Hi Rich,
Have you hooked these up  yet?
I have been momentarily 'tinkering' with these devices - We use them in our equipment to convert RS232 ModBus to ModBus/TCP. They are the same units AFAIK, except with different firmware. The utility used to 'program' or rather, configure them is windoze based and relies heavily on .net from the OS. - I find that rather annoying. So, long story short; I wish to pursue configuring them by using a shell (bash) script from a *NIX box to modify the configuration records. Also being able to update the firmware when necessary is useful since the later firmware include a web based browser interface to permit configuration. You could also customize this....
So, presuming you have it connected to a CAN bus of the ECU / automobile system; you can implement a browser based interface to display/modify required information?
I suspect more information can be had from the Lantronix company?
I'll post more as I get more familiar with this device since I have to develop a quick configuration utility for production  to use.
Simon

rich.carroll

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Re: Very high quality CAN BUS adapters at super price
« Reply #2 on: June 23, 2017, 12:20:19 AM »
Sorry, I have put this project on the temporary shelf.  Two projects with higher priority and the imminent move to Nevada seem to be consuming my time.  I'll let you know when I have something to report on these.
Rich Carroll                           rc@rc.to