Re: CBM Drive Mechanisms

From: William Levak (wlevak_at_cyberspace.org)
Date: 1999-08-12 01:36:06

On Wed, 11 Aug 1999, Nicolas Welte wrote:

> No, Bill, it's the spindle motor. The stepper motor is always connected
> directly to the drive's main board.

I checked again. You're right
 
> I didn't say this. I said that the WP LED is connected to the spindle
> motor control PCB, and it was on the Chinon drive.

OK, but this causes further problems.
 
> 250448 has an input for the track 0 sensor, it's mostly disabled by a
> short to GND (It was via J3, I think), but otherwise connected to PA0 of
> the bus VIA. The ROMs 251968-01 and 251968-02 have support for this
> signal. The 1541-II has the GND connection to PA0 left to enable this
> board to work with the two above mentioned ROMs. But the drive was only
> shipped with 251968-03 which had the sensor support removed.

It's 250442 and 250446 (1541A) that have the input and it is jumpered out
by J3 and it was shipped with the drive without the sensor. 

250448 (1541B) has the power for the track 0 sensor, but where does the
output signal go??
 
> > It appears then that the same Newtronics D500 drive mechanism is used on
> > all 1541 drives, only with different connectors and the track 0 sensor
> > removed on some.
> 
> I agree with you here, but the sensor probably doesn't have to be
> removed. Like on my 250442 board, where there's simply nothing useful
> connected to the track 0 sensor pins.

So why connect power to the sensor (on the 1541B) if the output goes
nowhere??


-
This message was sent through the cbm-hackers mailing list.
To unsubscribe: echo unsubscribe | mail cbm-hackers-request@dot.tcm.hut.fi.

Archive generated by hypermail 2.1.1.