Thank you Duane for your super fast reply! My dongle is pin compatible to openocd by now (I just added high speed level shifters to support targets from 1.2V to 3.3V with TCK speed greater than 30MHz). You said I'd have to set jtag clock speed to zero to enable adaptive clocking, ok, but as I am currently not reading the RTCK signal from the target, OpenOCD can't know the clock speed of the target. My question is how to tell OpenOCD what's the current clock speed of the target? Best regards Rik _______________________________________________ Openocd-development mailing list Openocd-development@lists.berlios.de https://lists.berlios.de/mailman/listinfo/openocd-development