I have finally tested the interface chip. The TDI signal ( output from
emulator ) is work fine. The TDO from the target seem to be toggling but
the output is not changing. So I will be checking the PCB board to make
sure that it is not shorted.

Thank you to Greg for your suggestion.

Best Regards
Tony

Hello Greg,

>How about measuring TDI & TDO ?

That is what I am planning to do. I am going to measure the 74HC244 input
and output of the TDI and TDO signal.

Thank you
Tony

Hello Tony,

How about measuring TDI & TDO ?
Compared to the clock's edge you can see what's going on.
Anyway we also exchanged a driver chip on an emulator
- means it's not impossible that it is broken.

                                Regards Wolfgang.

I recently bought an emulator from China, it is a "TDS510 DSP USB2.0". CCS
can't initialise the CPU, so I tested the emulator with xdsprobe.exe ( the
targetis a F2808 CPU on a board that was working fine with a Spectrum's
XDS510 emulator and the target PD is connected to 3.3V ). I got the
following result, 

The test for the JTAG IR instruction scan-path length succeeded.
The JTAG IR instruction scan-path length is 38 bits.

The test for the JTAG DR bypass scan-path length succeeded.
The JTAG DR bypass scan-path length is 1 bits.

-----[Perform the scan-path given data test on the JTAG
IR]------------------

This scan-path test uses blocks of 512 32-bit
words that repeat the data pattern 0x5533CCAA.

This scan-path test will be applied just once
using the first 1 of the 10 different test-cases.

Starting the Given Data Test.
Test 1 Word 0: scanned out 0x5533CCAA and scanned in 0xFF77CDBA.
Test 1 Word 1: scanned out 0x5533CCAA and scanned in 0xFF77CDBA.
Test 1 Word 2: scanned out 0x5533CCAA and scanned in 0xFF77CDBA.
Test 1 Word 3: scanned out 0x5533CCAA and scanned in 0xFF77CDBA.
Test 1 Word 4: scanned out 0x5533CCAA and scanned in 0xFF77CDBA.
Test 1 Word 5: scanned out 0x5533CCAA and scanned in 0xFF77CDBA.
Test 1 Word 6: scanned out 0x5533CCAA and scanned in 0xFF77CDBA.
Test 1 Word 7: scanned out 0x5533CCAA and scanned in 0xFF77CDBA.
The details of the first eight errors have been provided.
The utility will now report only the count of failed tests.
Test suites performed: 1, skipped: 0, failed: 1
Some of the 32-bit data values were corrupted - 49.9 percent.
Finished the Given Data Test.
The JTAG IR given data test has failed.

-----[Perform the scan-path given data test on the JTAG
DR]------------------

This scan-path test uses blocks of 512 32-bit
words that repeat the data pattern 0x5533CCAA.

This scan-path test will be applied just once
using the first 1 of the 10 different test-cases.

Starting the Given Data Test.
Test 1 Word 0: scanned out 0x5533CCAA and scanned in 0x7F33CCFE.
Test 1 Word 1: scanned out 0x5533CCAA and scanned in 0x7F33CCFE.
Test 1 Word 2: scanned out 0x5533CCAA and scanned in 0x7F33CCFE.
Test 1 Word 3: scanned out 0x5533CCAA and scanned in 0x7F33CCFE.
Test 1 Word 4: scanned out 0x5533CCAA and scanned in 0x7F33CCFE.
Test 1 Word 5: scanned out 0x5533CCAA and scanned in 0x7F33CCFE.
Test 1 Word 6: scanned out 0x5533CCAA and scanned in 0x7F33CCFE.
Test 1 Word 7: scanned out 0x5533CCAA and scanned in 0x7F33CCFE.
The details of the first eight errors have been provided.
The utility will now report only the count of failed tests.
Test suites performed: 1, skipped: 0, failed: 1
Some of the 32-bit data values were corrupted - 49.9 percent.
Finished the Given Data Test.
The JTAG DR given data test has failed.

I tested the board with -c

When the test data is 0xFFFFFFFF there was no Error, 100% pass.

When the test data is 0x00000000 the first test suit fail but the
subsequence test suit pass.

It seem to me that the emulator has difficulties in writing alternating 1
and 0, and the 0 is read in as 1. The emulator interface chip is a
74HC244. I believe the 74HC244 is broken.

Can anybody give me some suggestion, please.

Best Regards and thank you in advance
Tony