Using emulator on TMS320F28335

Hi Vincent,

On your custom board, have you implemented an on-board emulator (like the xds100v1 or xds100v2 like on some of C2000's EVM boards) or have you placed a JTAG header for usage with an external emulator?


Thank you,
Brett

I have placed a JTAG header for usage with an external emulator.

Vincent,

I would recommend checking some generic bring-up issues first:
1) Verifying your power rails are good
2) Ensuring that, on your custom board, there is a pull-down resistor on TRSTn
3) Check the status of XRSn when the C2000 device is powered

What C2000 MCU are you working with?


Thank you,
Brett

Hi Brett,

1)1.9V power rail: 1.87V is measured 

   3.3Vrail: 3.26V is measured

2) there is a 2.2K pull down resistor(see the aattached figure).

3)XRSn: 3.16V is measured 

Thanks,

Vincent4265.test2.pdf

Also, it appears there is some difference on the JTAG connections between my custom board and the EVM board. the schematics of the EVM board is attached. I am not sure if that will cause the problem.

0640.HDSP-Core28335.pdf

I am using TMS320FF28335

Hello,

Can you check, what is the voltage of TRST pin while connected to external emulator?

It should be high to work with the debugger.

Best regards,

Maria

Hi Maria,

Thanks for your help! I checked the voltage of TRST. Before the external  emulator is connected, TRST is 0V, and after the emulator is connected, it is 3.37V, which is a little surprising to me, because the power rail is only 3.26V. I suppose this 3.37V is suppied by the emulator, not from the board power rail.

Vincent.

Hi Vincent,

Based on the schematic you sent (4265.test2.pdf), I don't see anything obviously wrong.

It may be worthwhile to take a look at the XCLKOUT signal if you can.  If the core is booting correctly and everything is powered as needed, you should see a switching waveform (especially when the emulator is not connected).  I believe the frequency of this signal should by SYSCLK/4, but the documentation will tell you what it should be specifically.

What else is connected to "DSC-XRS#"?  Voltage supervisors?  Nothing?  Note that anything that can drive this line will need to be open-collector.


Thank you,
Brett

Hi Brett,

I dont't have an oscilloscope at hand, so I cannot measure the waveform, but I used the multimeter to measure the XCLKOUT's DC value, which is 1.63V. Assuming the duty cycle of the clk signal is 0.5, I can imagine that there is a waveform at this pin. The DSC-XRS# comes out from a LDO, shown in the attachment.

Thanks!

Vincent6835.test3.pdf 

The EVM's JTAG pin 6 is cut, while mine is not, and connected to GND. Is that a problem?

Vincent,

OK, based on your statements my thoughts are starting to lean toward it being a JTAG/emulation issue.

What version of CCS are you using?

Can you try "Test Connection" with your chosen target configuration? 

Can you try just connecting to the device (not just hitting the bug-button), but trying something like Method (1) in the following post:
http://e2e.ti.com/support/microcontrollers/c2000/f/171/p/328069/1151169.aspx#1151169


Thank you,
Brett

The 14pin JTAG connector is a keyed connector.  Pin 6 is the pin that is cut so that the emulator is not accidentally mated incorrectly.

-Brett

Hi Brett,

I am using CCS V3.3.83.20. I used your method 1,

")  This way has more steps, but you have control of each step.
a) From the CCS Edit view, right-click on the target configuration and click "Launch Selected Configuration". 
b) within the CCS Debug view's Debug window, right-click on the C28xx core and click Connect Target
c) load your .out file by clicking on the load icon.  (just above the 'u' in "Code Composer Studio - Device" in your screenshot).  HotKey: Ctrl+Alt+L
d) You should now be at Step29 in the workshop manual.  You can now run the code, single step, view memory, etc.  

"

but for step a), I don't see "target configuration" in the dropdown list of "EDIT".

I  clicked Debug-->Connect, but get an error message

Error connecting to the target: Error 0x00001200/-1135 Error during: OCS, Target,  Unrecoverable emulation error 

Thank you,

Vincent