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LPC900 series A/D

I notice that the EPM900 is supposed to emulate virtually all of the LPC9xx devices. Does this include the A/D converter on the 89LPC925? Is there any sample code that uses the A/D converter and the Real Time Clock? What is the analog input voltage range? The data sheet shows this as Vss-0.2V to Vss+0.2V. Surely this cannot be right.

  • "Is there any sample code that uses the A/D converter..."

    How about:

    http://www.keil.com/download/docs/207.asp

    www.nxp.com/.../AN10187_1.pdf

    www.standardics.nxp.com/.../user.manual.p89lpc924.p89lpc925.pdf

    "The data sheet shows this as Vss-0.2V to Vss+0.2V. Surely this cannot be right."

    Why do you doubt it?

  • The first reference is for a data logger that records the status of ports 1 and 2 and has nothing to with the A/D converter.
    The second reference is an application note on using the on-chip comparators for sigma-delta and dual slope A/D conversion.
    The third reference is to the users manual (not the data sheet) and has no information about the electrical parameters.
    I doubt the parameters in the data sheet because this sounds more like "Absolute Limit Values" and maybe the upper one is a mis-print and should be "Vdd+0.2V". Since it is unlikely that an on-board A/D that doesn't have a negative power supply or an external reference voltage can process negative voltages, this would mean a dynamic range of 0.2V. I have my doubts. If you examine the schematic of the Keil MCB900 board it includes a potentiometer that can feed an analog voltage of up to 3.3V into the Micro.