Motorola MC9S12DP256, CML12S-DP256 manual Tips and Suggestions

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Tips and Suggestions

Following are a number of tips, suggestions, and answers to common questions that will solve many problem users have with the CML12SXXX development system. You can download the latest software from the Support section of our web page at:

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Utilities

∙If you’re trying to program memory or start the utilities, make sure all jumpers are correct.

∙Be certain that the data cable you’re using is bi-directional and is connected securely to both the PC and the board. Also, make sure you are using the correct serial port.

∙Make sure the correct power is supplied to the board. You should only use a 9 volt, 200mA minimum adapter or power supply. If you’re using a power strip, make sure it is turned on.

∙Make sure you load your code to an address space that actually exists. See the Memory Map if you’re not sure. The MEM_EN and ECS options change the memory map.

∙If debugging under Mon12, make sure you're not over-writing internal RAM used by it.

∙If you’re running in a multi-tasking environment (such as Windows™) close all programs in the background to be certain no serial conflict occurs.

Code Execution

∙Under Mon12, breakpoints may not be acknowledged if you use the CALL command. You should use one of the GO command instead.

∙Check the Autostart mask and reset vector located in EEprom at 0xFEC - 0xFEF. These 2 words contain the enable mask and address where user application execution will begin when the unit is powered on.

∙When running your code stand-alone, you must initialize ALL peripherals used by the micro, including the Stack, Serial Port, and pseudo Interrupt vectors etc.

∙You must either reset the COP watchdog timer in the main loop of your code or disable it when not running under Mon12 or BDM mode. The micro may enable this by default and if you don't handle it your code will reset every few 100ms.

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