Discussion created by ROBERTO BERNER on Jan 22, 2009
Latest reply on Aug 25, 2010 by ROBERTO BERNER
Hello friends !

I have experience using the DEMOQG board and I had use it to program my final application boards by using the 6 pin BDM on-board connector. Never had a problem with the QG family and BDM.

I have a new design in a board using  MC9S08QE128 , the 80 pin version. My first time with this chip. When I received and assembled the first prototype board, I really never expected to have bad results trying to program the chip, but it happened.

The P&E micro DEMOQE board comes with a MC9S08QE128 chip mounted in a piggyback socket board. The chip is the 64 pin version, and not the 80 pin version that I am actually using in my prototype. I think that it should work the same :smileyhappy:

My prototype board has a 5 pin connector that directly brings just the two lines BKGD and RESET from pins 80 and 79 of the QE128 chip. There are no on board pull-up resistors or any other component connected to these two pins. So there is no interference possible because of sharing the pins with the rest of the circuit. The other connector pins are for external VCC and GND, so the programming board provides the energy during programming.

A jumper allows the user to select if the 3.00 V power for the MCU chip is taken from the application board local voltage regulator, or is taken from the mentioned external programmer connector. The only thing the external programming power supply "sees" on my board, is the QE128 power pins and two decoupling capacitors, one 100nF in parallel with 10 uF electrolytic, close to the QE128 chip. All of the power pins of the chips are used, VCC, VCCAD , VSS, VSSAD, VREFHI, VREFLO.

Using CodeWarrior 6.2 , the DEMOQE perfectly programs the piggyback chip that is inserted in the demo board and that comes provided in the box. If instead, I unplug the 64 pin chip from the board, and use the BDM extension cable to my programming connector, the DEMOQE board starts programming normally, recognizes the board via USB, but is unable to program my 80 pin chip on my final application board.

To my knowledge, there are no shorts, or missing connections. I checked this with a co-worker. The pins 63 and 64 on the DEMOQE board are connected to the 79 and 80 pins on my board, so I am using the same signals that he 64 pin version uses, exept that there is a less than one foot long flat ribbon cable between boards. The 3.6 V from the DEMOQE board can be measured correctly in all VCC connected pins of my 80 pin chip.

I thought a failed chip, so I took a second prototype board and installed another fresh 80 pin QE128 on it. Just the chip, the programming connector and the voltage source selection jumper. The rest of the board is not populated at all. Not a single component. The flat ribbon cable, connectors, etc. have been tested with a multimeter for pinout and also to verify that the pins on the DEMOQE board are connected to the corresponding pins on the application board. Same problem.

Finally, it sounds to me like that for some reason the part is not entering background mode.

Do you have any ideas or similar experiences ? What I am doing wrong ?

Thank you !