Newsgroups: comp.robotics
Path: brunix!sgiblab!uhog.mit.edu!news.media.mit.edu!fredm
From: fredm@media.mit.edu (Fred G Martin)
Subject: Re: Miniboard Kits from SDRTFT
Message-ID: <1994Apr12.032534.27701@news.media.mit.edu>
Sender: news@news.media.mit.edu (USENET News System)
Organization: MIT Media Laboratory
References: <steve-110494223450@fuzbat.pgh.pa.us>
Date: Tue, 12 Apr 1994 03:25:34 GMT
Lines: 27

In article <steve-110494223450@fuzbat.pgh.pa.us> steve@info.pgh.pa.us
(Stephen D. Cohen) writes: 

>     One unidentified (and unbeknownst to me) feature of the board was a
>space for a Dallas Semiconductor DS1233 and a capacitor in place of the IRQ
>button.  I don't know for sure, but I'm guessing that it is a reset
>controller to handle the power on and off situations to prevent EEPROM
>erasure problems.  If this is the case, I think I would have prefered to
>have the reset parts instead of the IRQ button.  I have plenty of other
>opportunities to interupt the processor. :-)

Mark Reeves is distributing the new "Mini Board 2.0 Extended."  From
the documentation file cher.media.mit.edu:pub/miniboard/docs/mbextend.txt:

  * if IRQ button is not installed, a Dallas Semiconductor DS1233
    "econo-reset" chip may be mounted instead.  This chip assures
    correct power-on reset operation of 6811 for "mission critical"
    applications.  (Most of the time the 6811 boots properly when
    power is applied, but the DS1233 may be used to insure that it
    -always- boots properly.)


Cheers,
Fred

Fred Martin | fredm@media.mit.edu | (617) 253-5108 | 20 Ames St. Rm. E15-320
Epistemology and Learning Group, MIT Media Lab     | Cambridge, MA 02139 USA
