Parallel IOs

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>from the help line
> I am currently experimenting with an ARMitePRO for a
> project where I need both D/A conversion and D/A conversion
> without using additonal external chips.
>
> The problem is the D/A conversion. Is there a way to
> group digital outputs (10 of them) to be a single port
> output? Currently for D/A conversion I am using a
> routine to extract bit-by-bit the values of a 10 bit number
> and output them one at a time to an output pin. This
> takes too long and generates noise.

You can write directly to the 32 bit ports. Details on their operation in the
User Manual for the LPC2103 (links from the help pages).

It allows you to write directly to 32 bits of Port 0. Use the Fast IO
registers, as that is how the part is configured.

You can also access them as individual bytes, but as you wanted 10 bits, you'll
have to maintain the state of pins you use as outputs when updating those last 2
bits.

On the SuperPRO and ARMweb, there is a 10 bit DAC available.

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Thanks, I broke down and measured the frequency of the squareware generated from
SET, CLR,..., it is a quarter of the processor clock frequency. I guess it takes
two cycles for a CLR and SET.

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that's HIGH/LOW, not CLR SET sorry