unprogram fuse-how?

Go To Last Post
4 posts / 0 new
Author
Message
#1
  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

about 2343

I need to unprogram the RCEN fusein order to use the external clock- how do i do it?
i use asmpack 1.3 and studio to program the chip.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

You need to be using a 'parallel' programmer. The fuse bits are not accessable using serial programming methods. The parallel programmer I use has it's own application, and a seperate drop down menu to allow fuse bits to be set/reset.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Hey Shaun, I think you're wrong. Page 41 of the datasheet for the 2343 gives the low voltage serial command to set/reset the RCEN bit. No need for parallel progarmming.

admin's test signature
 

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Hi!

Chris is right. Fuses are generally accessible through low-voltage programming, but a few aren't... An obvious example is the SPIEN fuse, which enabled/disables the SPI interface used to do low-voltage serial programming :) Programming of the fuse bits is generally well documented in the datasheets for the respective parts. It's a good thing to be very sure of what you're doing before you set the RSTDSBL fuse available on some devices too, because RESET is needed for in-system programming.

Have I clarified, or just confused you more? Hope the former.

Best regards,

Morten, AVR tech. support, Atmel FAE

admin's test signature