Re: [avr-libc-dev] Question on IO header policy

[Joerg Wunsch]

As Weddington, Eric wrote:

> In doing a search of the latest datasheet for those devices, the
> requested names (UCPHA0 and UCPHA1) are *not* found on the datasheet.

At least, they used to be mentioned in older datasheets.  The point
here is: UCSRnC has dual meaning, depending on whether the USART is
operating in USART or in SPI mode.  In USART mode, these bits
determine the frame size, while in SPI mode, they describe the SPI
phase situation and bit order.

I just downloaded the latest datasheet, and still, both bit names
*are* present there.  Go to the "Register summary" page, and you'll
notice there are two page numbers associated with these registers.
Follow both of them, and you'll see two different descriptions (with
different bit names) of these registers...

So bottom line, yes, we should have both definitions.  It doesn't hurt
much, we've been keeping aliases of older names in our header files
already in the past, so when we switch to XML-generated headers, we
have to handle alias names anyway.  For our own headers, that will
happen at the intermediate XML level that is needed for legal purposes
anyway (so we can store some XML file in our repository), for the
ATmegaXX4, we can simply import the Atmel-provided alias.

-- 
cheers, J"org               .-.-.   --... ...--   -.. .  DL8DTL

http://www.sax.de/~joerg/                        NIC: JW11-RIPE
Never trust an operating system you don't have sources for. ;-)