Problem with a LPC2148 based board

Check out the SFE “Uber board” schematic, that has a JTAG connector on it.

Does the oscillator start ?

Also try to slow down the JTAG or use 10K resistors, may be the 100k resistors are too high for the speed you are using.

Giovanni

You could check the oscillator with a logic probe or RF probe, it’s quite easy to make one. Or, listen for the signal on a SW radio.

Leon

Yes, running the bootloader. This would give you evidence of correct startup and stable operations.

Giovanni

Yes, you just need to add a level translator.

You need to hold P0.14 low while Reset is low to enable the boot loader.

To enable JTAG you need a weak pull-down resistor on P1.26.

This stuff is in the data sheet and the user manual.

Leon

Have you checked that they are actually connected to the LPC2148 pins and are working properly?

Leon