A1200 RTC Alarm under WB3.0

[Hodgkinson]

Hi folks,
I’m tinkering with the idea of using the "ALARM" output pin from the RTC IC in my A1200 to shut down a to-be-added ATX PSU. Does anyone know whether setting the alarm in the clock in WB actually sets the time on the RTC IC itself, or does the system just compare the RTC time to the set alarm time? On a more practical note, does having the alarm turned off in WB also turn the alarm off on the RTC IC (Heh, if it didn’t the system might start doing some of XP's tricks...)?

The idea is that I could then set the A1200 to shut itself down at a set time (Wouldn't that be cool...?), and, perhaps, with a little program to set the alarm time to the clock time, turn the A1200 off via software.
Having all the serial, parallel, expansion, and clock ports occupied means I can't just write to a port, I’ve got to steal a unused output from elsewhere...

Comments appreciated,
Hodgkinson.

PS. Does anyone use a "Head-park" program for their HDD prior to cutting the power? Is it recommended or is it unnecessary? Or, as I've been reading, does it depend on whether the HDD platter arm swings by itself in the non-data area of the disk when power is removed?

[Hodgkinson]

Actually, yeah, thats the one port im not using, and I doubt i'd manage to lay my hands on enough external drives to get to that point before I go to Uni next year. Programs on Aminet? Any suggestions which ones?

Thanks,
Hodgkinson.

[Hodgkinson]

A ~200MB 3.5" drive that I recently took to bits does...Anyone any ideas re IBM laptop drive model number DTNA-22110?

[Hodgkinson]

Thanks for the replies.
On the basis of me having absolutely no progamming experiece with Amigas, I think i'll have a look at the floppy drive appoach for turning the system off. Looking the the RTC chip on the Blizzard 1230, actually getting to the IC pins could be a issue.
Oh, re the output, I think it might say somewhere that its a audio tone of some frequency. Wouldn't be too difficult to rectify and smooth the signal and use it to control the ATX PSU, though.

Re the SEL2 line on the external floppy port, im a bit consered with regards to how the system detects which floppy drives are present. Espicially if I decide to add a DF1 to the system. Besides, how come SEL3 wasn't used?

Re HDD's with stepper motors...I did actually take one apart a few years ago...We've still got the platters somewhere as keepsakes...

Hodgkinson.