Debugging of MC9S08GT60 with cyclone pro

[praveen]

We are using MC9S08GT60 for your project. We are using cyclone pro for programming and debugging (in circuit).  For your project we are using RST, IRQ pins. How can we use the debugging and programming mode (in circuit) when we required for RST, IRQ pins for my program.

At present we are using 16 pin connecter of cyclone pro to program.

Pins that we are connecting to the micro controller are follows. 2nd n of cyclone pro to GND of mc, 4th of cyclone pro to RST of MC, 6th of cyclone pro to IRQ of mc, 8th pin of cyclone pro to PTAo of mc with 10k pull up, 12th pin of cyclone pro to PTCo of mc with 10k pull up, 13th of cyclone pro to XTAL of mc, 14th pin of cyclone pro to PTC1 of mc, 15th pin of cyclone pro to VDD of mc with 10k pull up.

For debugging in BDC mode we have to connect the 4 pins to mc as we are using in circuit debugging. Please send me details how we have to connect the BDC and programming with cyclone pro with only one connecter and also the check the connecting we made are proper.

[Wings]

"At present we are using 16 pin connecter of cyclone pro to program."

You are??? Unless there is another side of the S08GT family that I'm not aware of, you can only program that chip via the BDM port. Forget the 16-pin connector.

Also, you can go ahead and use the IRQ in your app on the GT60 since it is not used with the BDM in any way. Almost the same is true for RESET. As long as you have a passive pullup on RESET your app should be able to share that pin with the BDM. The thing you have to look out for is in sharing the PTG0/BKGD/MS pin. If you use this pin as an input it also should have a passive pullup and should not be driven high by an active driver in your external circuitry, nor should it be driven low coming out of a reset. If you use this pin as an output you also need a passive pullup present at least while the Cyclone is present. Best bet is to not use this pin at all, just let the Cyclone have it.


Did this help, or did I totally misunderstand your question?

[peg]

Hi praveen,

In fact the connection to RST within a BDM interface is entirely optional.

The only connections you need are power and BKGD.

Regards

Peg

[Geezer]

BDM reset optional? Don't use it and the darned thing may work, mostly!

- RESET is a sure-fire way for an external BDM pod to catch and force a run-away CPU back to sanity.
- HCS08 derivativs are allowed to drive this pin low, informing a BDM device that an internal problem occured (watchdog, LVD)
- the BKGD pin sets the BDM/RUN mode, as sampled on the rising edge of RESET. Most BDM devices try to control that sequence somewhat carefully (although some fail when BUSCLK is very low, but that's another story...)

Other than that, I always agree with Peg. :smileywink:

Al

[peg]

Hi Al,

The BDM pod must be designed to cope without a reset connection if it is to handle the QG.

So a GT with no reset connection has to be no worse than the BDM connection with a QG.

In fact it is better because at least blank entry is handled by a COP reset, unlike a QG.

See:

http://forums.freescale.com/freescale/board/message?board.id=8BITCOMM&message.id=3810

Of course make the RST connection if at all possible. It should always be electrically possible as, as you point out, it has to handle the MPU driving RST low anyway.

Regards

Peg