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Applies to: MCB2100 Evaluation Board


Information in this article applies to:


I'm using the Keil MCB2100 Board together with ULINK. Whenever I start the debugger, I get a message box with the following:

Memory Mismatch!
Address: 0x00000020
Value = 0xB0
Expected = 0x58

What can be wrong?


It appears that the device is in Serial Flash Download Mode and the Interrupt vector gets redirected.

Check to see if the jumper settings match the default setting. The MCB2100 Board is shipped with the following configuration:

Jumper       State    Description
J1 - ISP      ON      Enable In-System Programming via COM0.
J2 - AV       ON      Connect POT1 potentiometer to AIN0.
J3 - 3.3V     ON      Connect 3.3V to CPU.
J4 - 1.8V     ON      Connect 1.8V to CPU.
J5 - V3A      ON      Connect analog reference voltage to CPU.
J6 - LED      ON      Enable Port1.16 - Port1.23 LED's.
J7 - INT1     ON      Enable INT1 Push Button.
J8 - ETM      OFF     Disable Embedded Trace.
J9 - JTAG     ON      Enable JTAG interface.
J10 - RST     ON      Enable Reset via COM0.
J11 - CAN     ON      Enable CAN driver.
J12 - RD1     ON      Connect RD1 CAN receiver input.
J13 - RD2     ON      Connect RD2 CAN receiver input.

If J1 and J7 are OFF, the LPC21xx device may go into Flash Download Mode on Reset.

A similar problem may occur if you have connected the MCB2100 COM0 port to a PC. In this case disconnect J1 and J10.



Article last edited on: 2006-09-11 15:16:49

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