Question: Is it possible to somehow disable the KX8's monitor mode by means of an application loaded into its flash memory?
My setup as follows: I built a MON08 circuit as per circuit on page
193 of 68HC908KX8.pdf. I used a 74HC04 inverter with 9.8304MHz crystal, and constructed the circuit on Veroboard. All voltage levels on the device measures OK, as well as the clock signal. I proceeded to upload the bootloader as contained in AN2295 using prog08sz, but never managed to get it working in conjunction with hc08sprg.exe (HC08 never ACK'ed on power reset). I then erased the device and compiled a small test program derived from AN2616 page 26, using Metrowerks CodeWarrior.I then uploaded the file named P&E_FCS.abs.s19, and straight after that I lost all control with the device from within prog08sz. I could not establish a connection with the device again through the MON08 interface. Even in Hyperterminal I do not see double echo characters coming back from the micro, only 1 byte is echoed back. I checked my voltage levels on IRQ1, etc, but to no avail. I inserted another virgin device into my MON08 circuit, and it functions without problems. But the original device seems to be unable to enter into monitor mode.
Surely uploaded firmware should not preclude the use of the monitor mode, especially if one presets IRQ1, PTA0, PTA1, PTB0 and PTB1 externally, and use an external oscillator? Why would this upload cause one to lose control of the device in monitor mode? What did I do wrong? Please advise.
Thank you.