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Applies to: uVision Debugger


Information in this article applies to:


I'm using a Philips P89C664 device with 64KB on-chip Flash ROM. I want to debug my application with Monitor-51, so I have loaded the Monitor Code into the on-chip Flash ROM of this device.

Application Note 152: Installing and Using the Keil Monitor-51 says that von Neumann wired xdata/code memory is required to test user code. However, since the on-chip ROM is 64KB, the Philips P89C664 does not generate a PSEN signal. Is it possible to run the Monitor code in on-chip Flash? How can I test my code in on-chip Flash memory?


While it is possible to run the monitor in Flash memory, it is not possible to test applications in on-chip Flash ROM (since it is not von Neumann wired). The Philips P89C664 does not allow you to configure the ROM size, so you must use a similar device like the Philips P89C660 with less on-chip ROM space. You may then use the xdata memory area starting at address 0x4000 for testing your user application.

Some devices, like the Dallas 520 allow you to configure the on-chip Flash ROM size via an SFR. If you use such a device, you can set this SFR in INSTALL.A51 in the InitSerial routine to maximize the external address space.


Fore more information, refer to:

Article last edited on: 2005-07-20 16:01:46

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