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Operation incorrect: Why when testing serial I/O on actual system

Latest Updated:09/04/2009


When I tested the timers or serial I/O on actual system, the operation is incorrect. The problems happened only for f1 and f2 clock select. Target MCU : M16C/26A, M16C/28, M16C/29.


For M16C/tiny series MCU, a single PCLK0 bit is used to select f1 or f2 clock for few peripherals (Example : M16C/26A, PCLK0 control clock select for timers A, B and dead timer as a whole. M16C/28 and M16C/29, PCLK0 control clock select for timer A, B, S, dead timer, S I/O 3, S I/O 4 and multi-master I2C bus as a whole). Also, PCLK1 bit is used to select f1 or f2 clock for UART0 to UART2 as a whole. The IO Wizard engine does not do consistency check on f1 and f2 clock select for inter-related peripherals with respect to PCLK0 bit and PCLK1 bit. Scenario : On IO Wizard, user can select f1 for timer 1, f2 for timer 2. In this case, there is conflict on PCLK0 setting. User is advised to read and follow the advice comment stated in the config.c file, under the title area of each peripheral setting. Take into the consideration of whole system operation, user should decide choice of f1 or f2 and manually set PCLK0 and PCLK1 bit by themselves.
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