how to use partout

[jai]

Trying to use partout on a 32bit buffered port.

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out buffered port:32 DataBits = XS1_PORT_32A;

Here i have tried to output a part of the data (8 Bits, i guess its the LSB which will come out)

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partout(DataBits, 8, p1_data);

But this creates an exception.
Unhandled exception: ILLEGAL_RESOURCE, data: 0x00200000

XC Programming manual says:
The number of bits must be less than the transfer width of the port, greater than zero and a multiple of the port width,otherwise an exception is raised.

Here what is wrong with my code?

[richard]

Since DataBits is initialized with XS1_PORT_32A both the transfer width and the port width are 32bits. The partial output width you have tried to use (8) is not a multiple of the port width (32).

If you want to do a partial output of 8 bits then the port width must be either 1bit, 4bits or 8bits.

[jai]

Thanks richard, that makes it clear.

I was looking at Programming XC pdf.
On page 63,

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tailBytes = numBytes / 4;

Is this correct? Or is it supposed to be

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tailBytes = numBytes % 4;