AT Tiny Fuses and Low Voltage Programming

[Jiri Libra]

> Ahoj,
>
> niektore typy Atmelov maju low voltage programming a sucasne high voltage
> programming mode.
To maj snad vsechny AVR, krom tech nejmensich tiny(ATtiny11).
Pokud tim soucasne nemyslite v jeden okamzik ...

> Pri tych high voltage sa po nastaveni RSTDISBL bitu musi cip nejako dostat
> do programovacieho modu, kedze pin RST nie je pristupny. Robi sa to prave
> pomocou tych 12V, ktore treba priviest na pin RST pocas power-on resetu na
To zni logicky, takze nahodit 12V na RST, pak 5V na VCC, po case dat na RST
0V a zahajit standardni low-voltage programming. Jeste tam pisou neco o
synchronizaci, tim mysli asi synchronizaci se SCK, ne?

> cipe. V datasheete je par stran dalej presny popis (ala Atmel)
> programovacieho algoritmu.
Zminku o tech 12V na RST jsem nasel jen v teto poznamce.

>>If the RSTDISBL Fuse is programmed, then the programming hardware should
>>apply +12V to PB5 while the ATtiny12 in in Power-on Reset. If not, the
part
>>can fail to enter programming mode caused by drive contention on PB0
and/or
>>PB5.

Diky
Jirka