Other Parts Discussed in Thread: DRV8312, UNIFLASH, TMDSEMU110-U
Tool/software:
Hello,
I've inherited a project from a previous engineer. We have a custom circuit board with three (X, Y and Z) TMS320F28054M microcontrollers (80-pin LQFP), each controlling their own DRV8312 motor drivers.
The problem is that I only get the error "Error connecting to the target: (Error -1135 @ 0x0)" whenever I attempt to program through the JTAG pins the "Z" F28054M microcontroller using a "Texas Instruments XDS100v2 USB Debug Probe" through UniFlash (version 9.1) on the bench, with no motors connected to the board - but not the X or Y microcontrollers.
I can program the other two (X and Y) F28054M microcontrollers just fine. I can even program the Z microcontroller once every 100 attempts. But mostly, I get the following errors:
Error connecting to the target: (Error -1135 @ 0x3FF77B) The debug probe reported an error. Confirm debug probe configuration and connections, reset the debug probe, and retry the operation. (Emulation package 20.1.0.3372)
Or more rarely:
Error connecting to the target: (Error -1015 @ 0x0) Device is not responding to the request. Device may be locked, or the debug probe connection may be unreliable. Unlock the device if possible (e.g. use wait in reset mode, and power-cycle the board). If error persists, confirm configuration and/or try more reliable JTAG settings (e.g. lower TCLK). (Emulation package 20.1.0.3372)
Or more rarely:
Trouble Halting Target CPU: (Error -1156 @ 0x0) Device may be operating in low-power mode. Do you want to bring it out of this mode? Choose 'Yes' to force the device to wake up and retry the operation. Choose 'No' to retry the operation without waking the device. (Emulation package 20.1.0.3372)
I do notice that the VDD pins (6, 54, 73) are 1.895V to 1.908V on the "bad" Z microcontroller, whereas the X & Y "good" microcontrollers that do program successfully have their VDD pins at 1.910V to 1.920V. Otherwise their connections are identical to one another. The VDD pins are connected to 2.2uF. We are using the on-chip voltage regulator (VREG) to generate VDD by tying "VREGENZ" pin 71 to ground. The VDDIO pins (70, 38) are at 3.924V to 3.926V for all three microcontrollers.
More background: These are fresh production circuit boards whose design has not changed for over 2 years. The Z microcontroller is the only one that causes these errors on over 5 boards. I've also tried programming the same firmware on all three microocontrollers, yet the Z axis microcontroller continues to cause the "Error -1015 @ 0x0" as if my programmer isn't connected to anything at all.
Next Steps: I'll try to debug through Code Composer. Then I'm going to try to use a TMDSEMU110-U debug probe next to program the Z microcontroller through Uniflash to see if there's any success. Then I'll try to swap an X or Y microcontroller in the place for the Z microcontroller to see of the microcontroller itself is bad (unlikely if the error is on this specific microcontroller on the same position on multiple boards).
My questions: is there any direction I should focus on while debugging this issue? Is it a power issue, perhaps the Z microcontroller's output pins are driving too much current? Or is it a programmer issue? How can I increase the voltage on the VDD pins, and what factors could decrease their voltage? Is 1.910V some special threshold for the flash memory to function or something? I've also read the threads on:
