ATDF file says 0x62 for the low fuse, but the datasheet says 0x64. Any idea which is correct? Datasheet error?
This is messed up. There are datasheets with 0x62 and 064. There are ATDFs with 0x62 and 0x64. Let's look at Atmel.ATtiny_DFP.1.3.229.atpack from http://packs.download.atmel.com/ :
grep initval ATtiny2313* | grep LOW
ATtiny2313.atdf: <register caption="" name="LOW" offset="0x00" size="1" initval="0x64">
ATtiny2313A.atdf: <register caption="" name="LOW" offset="0x00" size="1" initval="0x62">
The low fuse=0x64 has the system clock running at 8MHz. This is the factory default [also the CLK/8 fuse is active: which makes the clock default actual be 1MHz].
When the low fuse is 0x62, then the system clock is 4MHz. Table 2: page 23 of the PDF datasheet file for ATtiny2313.
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