Should I use GPIB or CAN for automotive radio testing station?

Hi, guys,

I am designing a interface box of a testing station for automotive radio testing. The testing station setup will be:

radio DUT <==> Interface Box <==> Testing Equipments
_________________^_______________^
_________________|| CAN or GPIB?___|| GPIB
_________________<====> PC <====>

It is desired to have automatic load switching in the interface box. I need some suggestion on which protocol to use for controlling the interface box. The protocols I am looking at are GPIB and CAN. GPIB is wider used in testing equipments and CAN is widely used in automotive electronics.

Could anyone help me to compare these two protocols in terms of
1. which one is more suitable for my application.
2. difficulty of implementation in hardware, including design and testing.
3. difficulty of software coding. I need to write driver for the uC in my interface box.

Thank you very much!

-= madtank =-

Re: GPIB or CAN

Frankly, I wouldn't bother with GPIB or CAN ..
Use standard serial port (RS-232) or if you want to connect more devices you can implement half/full duplex RS-485 (one/two twisted pairs respectively) ..
If you use off-the-shelf termnal software such as for example:
h**p://www.rfinnovations.com.au/Uploads/Images/RFI-Interm%20Rev1.1(1).zip (change ** to tt, copy and paste the whole thing to the address icon)
you can write ASCII or HEX strings as commands and send them to Interface Box by clicking on single button ..
Regards,
IanP

Re: GPIB or CAN

Today normally all automotive units are equipped with CAN
CAN is basically use for on board communication with various other units within the vechicle
If you are planning to make a commercial unit (I am assuming that you are developing the radio DUT) then its better to have it equipped with CAN

If you are comfortable with CAN programming (or microcontroller programming which have CAN included) then it will be very easy to make your interface box
and program it

If the radio DUT is not made by you then its better to use the same protocol as which is used by DUT to communicate with the tester that will make your programming less complicated

Re: GPIB or CAN

Hi, IanP,

Thanks for your reply. In fact I can't agree with you more... However, it is one of the requirements to upgrade the old serial port based design to USB based design. Of course using USB to talk to the uC is one solution, but since we are going to integrate a USB-2-CAN transceiver board and a USB-GPIB transceiver in the loadbox anyways, I think it's easier to use CAN or GPIB so that I don't have to deal with the USB driver etc. That's how I came to the problem :]

Thank you for the tool! I will keep it in my toolbox

IanP said:

Frankly, I wouldn't bother with GPIB or CAN ..
Use standard serial port (RS-232) or if you want to connect more devices you can implement half/full duplex RS-485 (one/two twisted pairs respectively) ..
If you use off-the-shelf termnal software such as for example:
h**p://www.rfinnovations.com.au/Uploads/Images/RFI-Interm%20Rev1.1(1).zip (change ** to tt, copy and paste the whole thing to the address icon)
you can write ASCII or HEX strings as commands and send them to Interface Box by clicking on single button ..
Regards,
IanP

Click to expand...

Added after 3 minutes:

Hi, instruite,

the radio DUT is a product of my company, and they are equipped with CAN or J1850 bus. What I am developing is a tester box for the testing of our product. There will be a USB-CAN transceiver integrated in the tester box in order for the PC to talk to the radio.

I will probably go with CAN solution since my supervisor thinks it's better supported here, although I prefer GPIB more. I think it sounds cool to develop a tester box with GPIB support, making it like a professional testing equipment.

Could you give me some suggestion in choosing a proper microcontroller with CAN support? one concern is that I need to choose a yet general purpose microcontroller, so that 3~5 years later the micro will still be available for purchases.

Thank you very much~!

instruite said:

Today normally all automotive units are equipped with CAN
CAN is basically use for on board communication with various other units within the vechicle
If you are planning to make a commercial unit (I am assuming that you are developing the radio DUT) then its better to have it equipped with CAN

If you are comfortable with CAN programming (or microcontroller programming which have CAN included) then it will be very easy to make your interface box
and program it

If the radio DUT is not made by you then its better to use the same protocol as which is used by DUT to communicate with the tester that will make your programming less complicated

Click to expand...