ATXMega A1: Nr of clock sources contradictory

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Filename: doc8077
Version: 8077H"“AVR"“12/09

Chapter: 7. System Clock and Clock options

While the description in 7.9.4 suggests that five clock sources may be selected for the RTC, the figure 7-1. in contrast does not depict the presence of the implied additional prescaler providing TOSC nor the necessary additional input for the multiplexer whose output feeds the real time clock.

Further the the figure 7-1 does not show any signal labeled "Clkasy"

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Filename: doc8077
Version: 8077H–AVR–12/09

Chapter: 7.14 Register Summary - DFLL32M/DFLL2M

The table contains two entries labeled "COMP2" on offsets 0x06 and 0x07.
The bit positions of the entry on offset 0x07 are the same as on offset 0x04 where label "COMP0" is described.

[four separate threads now merged]

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Atmel seem pretty convinced it's (offset=) 0x06 in fact:

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C:\Program Files\Atmel\AVR Tools\Partdescriptionfiles>grep COMP2 ATxmega128A1.xml
                                        

Those .XML files are the ultimate "authority" (used by Studio for simulator, used by the assembler to generate the inc.def files, used by most C compilers to create their IO*.h files) so if you are in doubt about anything start by checking there.

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However, the documentation is contradictory in itself and in respect to the xml-file.
May be, this should probably better go into to the errata section.

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Filename: doc8077
Version: 8077H–AVR–12/09

Chapter: 7.13 Register Summary - Oscillator

The table does not name the bits 0 and 1 of the entry for DFLLCTRL.

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Filename: doc8077
Version: 8077H–AVR–12/09

There are two graphical statements which locate the clock source for the watchdog in two different places.

In chapter 2.1 Block Diagram, Figure 2-1. shows a block named "Watchdog Oscillator" in the upper right corner.
(It is furthermore unclear what the connection to the clock generation depicts, resp. what kind of information or energy it transports).

Contrary to that, Figure 7-1. in chapter 7.2 shows that the watchdog timer is feed by the 32kHz ULP oscillator (divided by 32) which clocks the brown-out-detection too.

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====================================================================================
C:\Program Files\Atmel\AVR Tools\Partdescriptionfiles>grep DFLLCTRL ATxmega128A1.xml
                                        

( why two threads about a virtually identical subject? or are you going to start new threads about every A1 documentation error? - if you do you might swamp this message board with threads! ;-))

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Sorry but see the moderator note I just made in one of your other threads. I'm locking this one before this gets out of hand.

You are aware of this thread I suppose?

https://www.avrfreaks.net/index.p...

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Quote:
( why two threads about a virtually identical subject? or are you going to start new threads about every A1 documentation error? - if you do you might swamp this message board with threads! Wink)

Hm. Despite I don't think that these posts cover the same issue, that's still a point. I you like (and have the means) you could shift them all to a new thread named "ATXMega A1 Documentation Errors".
Sorry, for the inconvenience.