AVR Butterfly JTAG Pins For General I/O
The JTAG-interface of the ATmega169 on the AVR Butterfly is enabled by default. While JTAG is enabled the four JTAG-pins PF4-PF7 (connected to PORT J402 of the AVR Butterfly) can not be used for general Input and Output. If JTAG debugging is not needed there are two possibilities to make those pins available.
- Disable the JTAG-Interface by Fuse
- Disable the JTAG-Interface by Software[Bascom code]
…
‘to disable JTAG
Mcusr = &H80
Mcusr = &H80
…
Taken from this article.
How to disable JTAG on RoboterNETZ.de.