Need help with MC68HC908AZ60A MCU

[TS33DDI]

Hi,

Can anyone clarify or explain why correct data needs to be enter on to buffer memory at address fff6 - fffc for a user to be able to read this MC68HC908AZ60A(QFP64) chip and could that be the reason why I'm getting errors telling me that the device does not respond in ISP mode? Interestingly, shorting the pins OSC1 and OSC2 allows a read but I can't be sure whether the data I'm getting is correct. Is there a setup recommendation for this chip and when would one need to set up the content registers(ff80,ff81,fe1c, & fe18)?

Thanks!

[Dataman (Neil Parker)]

Hello TS33DDI,

The Motorola/Freescale MC68HC908AZ60A MCU has a security feature where it requires known data to be located in the FFF6h to FFFDh address range in the buffer in order for the data on the chip to be accessible. It is basically a password which allows you to gain access to the data stored on the device.

Taken from our "General info" in our software:
To read a device, the buffer must be filled with correct data from address FFF6h to address FFFDh. Incorrect data at these locations will prevent correct access to the device.

For more detailed information on this feature please reference the device datasheet.

If you have any further questions, please post them here and we will do our best to get them answered.

Regards
Neil Parker
Dataman Programmers
Technical Support