MCF52236CAF50 - strange start problem

Tadas — Mon, 06 Oct 2008 21:05:09 GMT

Hello all,

I developed my first ColdFire board with MCF52236CAF50 mikro (I'm very newbie with ColdFire, sorry).

For testing I made a simple project using the CodeWarrior 7.1 and Processor Expert.

There are configured only 2 output pins (PTC0 & PTC1) and they are simple toogling in opposite manner in main loop.

Flash upload was made by EzPort (upload and verifying OK).

And now strange things - when asserting external RESET - program did't start at all, when powering board up with soft rise of Vdd - programm starts, but executes only about 3 milliseconds (controlled on output pins by oscilloscope, slightly differ from time to time).

If Vdd rises instantly, the programm didn't start, like with external RESET.

Pin RSTO shows normal behavior in all cases.

In case the programm starts, the CLKOUT pin shows normal clock frequency, as it is configured.

In case of fail start CLKOUT always gives crystal frequency (25 MHz).

Can anyone help me with this problem ?

Re: MCF52236CAF50 - strange start problem

Tadas — Fri, 10 Oct 2008 19:50:44 GMT

Thank you for help, folks :smileyhappy:

At last I found, that there wasn't JTAG_EN pullup in my board.

Now all works fine.

topic Re: MCF52236CAF50 - strange start problem in ColdFire/68K Microcontrollers and Processors

MCF52236CAF50 - strange start problem

Re: MCF52236CAF50 - strange start problem