CKDIV8 Fuse Bit and CLKPR Register: What Realtionship?

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  1. CKDIV8 Fuse Bit of the ATmega328-PU chip of ArduinoUNO is unprogrammed. It means that:

(a) System Clock (clkSYS) is equal fosc;
(b) The divisor factor is 1/1.
(c) The [CLKPS3:0] bits of CLKPR register are set to 0000.
(d) If we read the Low Fuse Byte, we will find Logic-H (1) at the CKDIV8 position.

  1. The CLKPS3:0 bits of the CLKPR register can be changed (and these are changed) to set the
    clkSYS at a desired frequency of: 1/1, 1/2, ... , 1/256. Say, we wish: clkSYS = fosc/8. The
    instructions are:
   CLKPR = 0x10;               //1 000 0000  enable change with MS-bit LH and all other bit at 0s
   CLKPR = 0x03;               //0 000 0011  division facor 1/8 with LL at MS-bit
  1. My question is:
    What logic value will we find at CKDIV8 position after reading the Low Fuse Byte?
    is it still 1 (LH) ? Why is it not 0 (LL)?
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the fuses are all "inverted" logic - a "0" means that the fuse has been SET.

Changing CLKPR does not change the fuse value.

CKDIV8 controls the initial value of CLKPR after RESET. If CKDIV8 is 0 (set), then CLKPR will be set to divide by 8...

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Thanks for the prompt reply.