LPC1549 - PINASSIGN15 - Reset Vaule of the Reserved fields

[pepoja]

Hi,

Please LPC masters, If you have a few minutes of free time, have look to the reset value of the register PINASSIGN15.
In UM10736, page 136, Table122 you can find Reset value: 0xFFFF FFFF ( Reserved byte also), but if I was trying to read in real MCU (LPC1549JBD64) I got value 0x0000 FFFF - Reserved bytes are 0x00!

What is wrong? User's manual or chip?

Thak you.

[victorjimenez]

Hello,

Thanks a lot for your carefully review of the SFR reset value. In actual usage, we don't read the reserve bit, because it's contain is none of meanings, and contain value is not determined. In documentation, we just give a "1" to these bits, but this doesn't mean it be "1". For these bits, we need avoid to read or write them.

Have a great day, 

Victor.

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[pepoja]

... "1" to these bits, but this doesn't mean it be "1" ... - It's georgeous!

If "1" doesn't mean "1" and "1" is not "0", what's mean "1" ??

No, it's joke only :-)

For this reserved bits is better write in datasheet '-' as reset value. That's all.

It's only small mistake.

Have a nice day.