MCF51JM128VLH datasheet by Freescale Semiconductor

MCF51JM128VLH Frequently Asked Questions (FAQs)

• What is the maximum operating frequency of the MCF51JM128VLH?
  The maximum operating frequency of the MCF51JM128VLH is 50 MHz.
• How do I configure the clock source for the MCF51JM128VLH?
  The clock source for the MCF51JM128VLH can be configured using the System Integration Module (SIM) registers. The SIM_CLKDIV register controls the clock divider, and the SIM_CLKSEL register selects the clock source (e.g., internal oscillator, external oscillator, or PLL).
• What is the purpose of the Low-Voltage Detect (LVD) module in the MCF51JM128VLH?
  The LVD module in the MCF51JM128VLH is used to detect when the voltage supply falls below a certain threshold (e.g., 2.5V or 1.8V). When a low voltage is detected, the LVD module can generate an interrupt or reset the device to prevent damage or data corruption.
• How do I use the DMA controller in the MCF51JM128VLH?
  The DMA controller in the MCF51JM128VLH can be used to transfer data between peripherals and memory without CPU intervention. The DMA controller is configured using the DMA_SAR (Source Address Register), DMA_DAR (Destination Address Register), and DMA_TCR (Transfer Count Register) registers. The DMA request signals from peripherals (e.g., UART, SPI, I2C) trigger the DMA transfer.
• What is the difference between the MCF51JM128VLH and the MCF51JM64VLH?
  The main difference between the MCF51JM128VLH and the MCF51JM64VLH is the amount of flash memory: the MCF51JM128VLH has 128 KB of flash, while the MCF51JM64VLH has 64 KB of flash. Both devices have the same peripherals and pinout.