I'm using a TMS320C6748 DSP with code composer and XDS200 emulator.
I was debugging my source code (only two instruction executed) where I have lost the connection with the DSP by the JTAG Interface.
After that problem, The DSP go in execution with the software versione downloader in the external nor flash memory, but It is not possible to connect code composer by XDS200 and JTAG Interface.
I have excluded a problem with the XDS200 Emulatore, becouse I have used a second one with the same result.
I have analyzed the electric board and I have identified the signal of TMS JTAG fixed to ground.
In the Product Description of the web page and datasheet, it is declared: "By default, the JTAG port is locked down to prevent emulation and debug attacks; however, the JTAG port can be enabled during the secure boot process during application development.".
Also, it is possible to read in other documents that there is an IOPU (IO Protection Unit) descripted in an specific document while the MPU is described in the technical reference manual.
I am interested to know:
1. The JTAG Port is locked only with TMS signal pulled down in the TMS320C6748 or all JTAG signals are pulled down?
2. Where Can I find the IOPU documentation?
3. Is There an additional tool that I can use to verify the protection status (Boot Secure, IOPU and MPU) of theTMS320C6748 in order to verify if the TMS signal is broken or if the DSP is in protection status?
4. Are there other quick trips that anyone can suggest?
