Which are the AVR8L devices?

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I see in a help screen, the comment:

    The displacement form of this instruction (LDD) is not available on AVR8L based devices

 

Elsewhere, I see generic comments about various other instructions: this instruction may not be available in all...check your specific device datasheet

Well, I'm using a Mega168, and the instruction is listed in the data sheet, so I assume all is well...but what are the  AVR8L devices?  I can't seem to find anything on the freaks regarding these (though I assume it means the tiny devices)--of course the poor forum searching doesn't help much & even Google search seems dry.

 

To add confusion, I ran into this recent table from Atmel :  (http://www.atmel.com/webdoc/avrassembler/avrassembler.wb_LDD.html)

 

(iiii)* LDD Rd, Y+q 0 ≤ d ≤ 31, 0 ≤ q ≤ 63 PC ← PC + 1

Notes: *The displacement form of this instruction (LDD) is not available on AVR8L based devices

 

Cycles:

 

Cycles

Cycles xmega

Cycles AVR8L

(i)

2

1/2*

1/2**

(ii)

2

1/2*

1/2**

(iii)

2

2/3*

2/3**

(iiii)

2

2/3*

N/A

 

 

But this table (iiii) somewhat infers (since only two "styles" are listed) it is not Tiny vs  non-Tiny, but Xmega vs  non-Xmega.  However, my mega168 datasheet lists the command (so I'm proceeding with that assumption).

....strange

 

 

 

When in the dark remember-the future looks brighter than ever.   I look forward to being able to predict the future!

Last Edited: Sun. Feb 12, 2017 - 04:39 AM
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Based on this comment in an old thread:

https://www.avrfreaks.net/comment...

 

Looks to me like the term AVR8L refers to the cramped/crippled Tiny's such as the Tiny10/11/12

 

All I could find from a Google Search

 

Jim

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avr-gcc finds it necessary to divide the "AVR" architecture into about 13 sub-architectures (plus special cases for legacy chips?)  You can see the list in the compiler directory xxx/avr/lib/*, and find a particular chip (at least in recent versions of gcc) by finding the matching "lib<chipname>":

BillW-MacOSX-2<10005> find . -name \*libatmega88\*
./lib/avr4/libatmega88.a
./lib/avr4/libatmega88a.a
./lib/avr4/libatmega88p.a
./lib/avr4/libatmega88pa.a
./lib/avr4/libatmega88pb.a
BillW-MacOSX-2<10006> find . -name \*libatmega328\*
./lib/avr5/libatmega328.a
./lib/avr5/libatmega328p.a
./lib/avr5/libatmega328pb.a

However, the gcc names don't match up with any Atmel names that I know of; I haven't seen "8L" before.  Perhaps that's the new "xTiny" architecture?

(and I don't think I've ever seen a nice table that goes in either directions.   Um...   http://www.nongnu.org/avr-libc/u... perhaps?)