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Information in this article applies to:

  • MCBx51 Evaluation Boards


The MCBx51 Evaluation Board is shipped with pre-installed Monitor-51 and Monitor-251 firmware. For the adaptation of chip-specific initialization, I need to reconfigure Monitor-51 and install it to the MCBx51. Must I also generate a Monitor-251 configuration?

Since the MCBx51 Board contains an address logic (PAL), it is unclear how to make a new Monitor-51 EPROM. Can you provide the steps for configuration?


You do not need Monitor-251 configuration if you plan running only 8051 devices on the MCBx51 board.

You may configure a new Monitor-51 for MCBx51 using the following settings:

Monitor Code  : 0xE800 - 0xFFFF
Monitor Data  : 0xDF00 - 0xE7FF
User Code/Data: 0x0    - 0xDEFF

For Monitor configuration:

  • Open a Command Prompt (DOS) Window and select the Monitor folder Keil\C51\MON51\.
  • Make the required extensions or modifications to the file Install.a51.
  • Then build the MON51.HEX file with the following command on the windows command line:
  • Load the file MON51.HEX to 27C010 EPROM using a standard EPROM programmer.

The DIP-switch Settings for running this Monitor on MCBx51 are:

  1. ON: Uart_INT select on-chip UART
  2. OFF: ext_Uart disable off-chip UART
  3. OFF: SRC/D2 connect A14 to EPROM
  4. OFF: PAGE connect A15 to EPROM
  5. ON: Monitor select RAM Mapping for user code
  6. OFF: 51/151 connect A13 to EPROM
  7. ON: MAP1 select 8051 mapping
  8. ON: MAP2 select 8051 mapping
  9. ON: LED select 8051 mapping
  10. OFF: A17 do not useselect 8051 mapping

Connect the serial cable from the PC to INT_RS232 connector on the board. Since the Monitor is configured for automatic baudrate detection, you may use a wide range of baudrates on your computer. Typically, a stable baudrate for 24MHz crystal is 38400 baud. However, the available baudrates depend on the device you use.

Last Reviewed: Thursday, January 18, 2007

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