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- Newsgroups: sci.electronics
- Path: sparky!uunet!snorkelwacker.mit.edu!bloom-picayune.mit.edu!athena.mit.edu!jory
- From: jory@athena.mit.edu (Jory Bell)
- Subject: Dallas Semiconductor Clock Chip
- Message-ID: <1992Jul22.200259.22871@athena.mit.edu>
- Sender: news@athena.mit.edu (News system)
- Nntp-Posting-Host: e40-008-12.mit.edu
- Organization: Massachusetts Institute of Technology
- Date: Wed, 22 Jul 1992 20:02:59 GMT
- Lines: 36
-
- I am presently working on a project which uses a 6811 and
- a clock chip as part of a timer which will be deployed
- in the ocean for up to a year at a time. The timer controls
- and instrument which takes water samples for climate
- change research...
-
- Anyway, I am using a 6811 and the Dallas Semiconductor
- DS1284 clock chip. Actually, using is a strong word, since I
- have had no success using the Dallas Chip.
-
- If anyone has any experience with the Dallas chip:
- After writing a more complete startup program, I eventually wrote a
- simple program to just write $0f to register 9 of the clock.
- This should turn on the oscillator (which is not on) and also the
- square wave output. It doesn't. What we checked:
- 1. The voltages on Vbatt and Vcc are 3 and 5 respectively.
- 2. the address and data pins are what you would expect.
- 3. CE is active low
- 4. OE is inactive high
- 5. WE is pulsing as one would expect for long enough
- 6. I tried several 1284's with several oscillators.
-
- I am completely stumped...
-
- So, if anyone knows about the 1284, I'd appreciate their
- comments and critiques...
-
- Otherwise, does anyone know of a different clock chip which
- incorporates exceptionally low power with some sort of alarm
- function which allows the chip to sleep until a preset alarm
- (preferably longer than the 1 week which the dallas can sleep
- for). The 50 bytes of (nonvolatile) memory on the dallas
- unit are also a nice feature...
-
- thanks bunches
- -jory (@athema.mit.edu)
-