topic Re: K60 FlexCAN demo problem in Kinetis Microcontrollers

K60 FlexCAN demo problem

UniversalTroope — Wed, 08 Jun 2011 20:04:08 GMT

I'm trying to run the FlexCAN demo on a Tower K60 board, with serial board. (MQX 3.7 and IAR EW-ARM 6.20)

It doesn't seem to work - data is apparently transmitted, but nothing is received. Also, I can't measure any activity on the CAN RX/TX pins in tower connector. I checked pin mux is ok. Also, I tried to fix for the e2583 errata, which seems to work.

// e2583

OSC_CR |= 0x01<<OSC_CR_ERCLKEN_SHIFT;

Any ideas? Can you successfully run the FlexCAN demo?

This is my output:

...

Data transmit: 155
FLEXCAN tx update message. result: 0x0
Data transmit: 156
FLEXCAN tx update message. result: 0x0
Data transmit: 157
FLEXCAN tx update message. result: 0x0

...

Re: K60 FlexCAN demo problem

UniversalTroope — Tue, 27 Sep 2011 17:13:29 GMT

New Kinetis board, same problem... Any ideas please?

Re: K60 FlexCAN demo problem

konrada_anton — Tue, 27 Sep 2011 17:57:05 GMT

What's your hardware setup? Is there another piece of CAN hardware you communicate with?

Re: K60 FlexCAN demo problem

jpa — Tue, 27 Sep 2011 20:08:52 GMT

I don't have much to add except: yes, I do have the Flexcan demo running (although I'm using Codewarrior 10.1) and note that the terminal output doesn't seem to tell us much. I just tried disconnecting the receiver from the CAN bus altogether and the terminal output keeps chirping away with the same message.

But with the receiver connected, I can see the messages coming in at a regular pace and can send a message to ID 0x123 and it is received by the K60 and printed to the terminal.

I know this is all obvious, but check to see that your frequencies match and that you've got the 3 pin connector on the TWR-SER wired up correctly. Note that the DB9 is for RS232, and doesn't get re-wired for CAN as it does with many Freescale development kits. I believe my hand-wired adapter goes J7 pin 1 to DB9 pin 7, J7 pin 2 to DB9 pin 3, and J7 pin 3 to DB9 pin 2.

JPA

Re: K60 FlexCAN demo problem

UniversalTroope — Thu, 29 Sep 2011 14:00:28 GMT

Thanks for the replies. I can't measure any activity on the CAN TX/RX pins in the tower connector (the white PCI-like connector), so I think it might be a hardware issue.

Re: K60 FlexCAN demo problem

UniversalTroope — Mon, 03 Oct 2011 17:38:40 GMT

A Freescale FAE has resolved the problem as a hardware issue with the CAN bus on my tower kit. The CAN bus works fine on my new kit.

Re: K60 FlexCAN demo problem

Abhitechmania — Tue, 15 Nov 2011 21:22:39 GMT

Hello,

I am also facing the same problem. The demo is running fine but I dont see any activity on J7 pins. What hardware changes have been suggested or can you tell me the version of the kit you are using now.

Regards,

Abhinav

Re: K60 FlexCAN demo problem

amish_M4 — Sat, 03 Dec 2011 19:12:04 GMT

Can someone explain the problem with the board? I think I am having the same issue here.

Re: K60 FlexCAN demo problem

unmannedrussery — Thu, 26 Jan 2012 08:49:45 GMT

*BUMP*

Does anyone (Freescale folks?!?!) have any further info on this? I'm having exactly the same problem. I would have expected the FlexCAN demo to work out of the box on the TWR K60N512, but I haven't been able to get it to communicate. Like previous posters, the terminal output says that everything is working fine:

*********FLEXCAN TEST PROGRAM.*********
Message format: Standard (11 bit id)
Message buffer 0 used for Tx and Rx.
Interrupt Mode: Enabled
Operation Mode: TX and RX --> Normal
***************************************

selected frequency (Kbps) is: 125
Data length: 1
FLEXCAN reset. result: 0x0
FLEXCAN initilization. result: 0x0
FLEXCAN mode selected. result: 0x0
FLEXCAN global mask. result: 0x0
FLEXCAN Error ISR install, result: 0x0
FLEXCAN Bus off ISR install, result: 0x0
FLEXCAN error interrupt enable. result: 0x0
FLEXCAN rx remote mailbox initialization. result: 0x0
FLEXCAN rx mailbox initialization. result: 0x0
FLEXCAN mailbox activation. result: 0x0
FLEXCAN RX ISR install. result: 0x0
FLEXCAN RX remote ISR install. result: 0x0
FLEXCAN tx remote mailbox initialization. result: 0x0
FLEXCAN tx mailbox initialization. result: 0x0
FLEXCAN tx mailbox activation. result: 0x0
FLEXCAN TX ISR install. result: 0x0
FLEXCAN TX remote ISR install. result: 0x0
FLEXCAN started. result: 0x0
Data transmit: 0
Data transmit: 1
FLEXCAN tx update message. result: 0x0
Data transmit: 2
FLEXCAN tx update message. result: 0x0

I've tried probing the CAN pins on the A Expansion Port, and the TX (pin 42) is just floating high with no data on it. I've stimulated pins 1 and 3 on TWR SER J7 with CAN data at 125kbps, and was able to view the data on Pin 41 using a logic analyzer, so at least my TWR SER must be configured correctly.

Additionally, I used the Memory viewer in my debugger to check the TX mailbox (memory location 0x400A4098), and am able to see the data value increment in sync with the one spit out on the terminal. However, the CANbus remains dead.

Any thoughts? I've spent the whole day messing with this, and would love to get this demo working!

Regards,

Robert

Re: K60 FlexCAN demo problem

unmannedrussery — Thu, 26 Jan 2012 10:33:33 GMT

Update... FIXED!

The problem is with the TWR SER jumper setup specified in TWRSERUM.pdf (or at least my interpretation of that setup). The table for J5 says shorting pins 1-2 "Put[s] CAN transceiver into sleep mode". This is actually incorrect.

Installing this jumper connects the "S" pin on the transceiver to ground, which puts the transceiver into normal operation or high speed mode (see pg. 4 of the datasheet http://www.nxp.com/documents/data_sheet/TJA1050.pdf).

So for this demo to work, you must short pins 1-2 of J5 on the TWR SER board. I had tried this earlier, but was doing it with a loose piece of wire (I'm short on 0.1" jumpers), and must not have had the two pins shorted effectively.

Regards,

-Robert