[time-nuts] microcontroller based IRIG generator

[Morris Odell]

I did this successfully a few years ago using an AVR 90S8535 to generate  
IRIG B so that I could use a vintage nixie IRIG display with a Trimble  
Lassen IQ GPS receiver that spoke NMEA IIRC.

I used one of the counters in the AVR to generate the 1 KHz carrier, read  
the serial output of the receiver with the USART in the AVR, translated it  
and generated a binary IRIG code to modulate the carrier by switching the  
bottom of a resistive divider up and down.

It wasn't too hard as I recall, and I was much less experienced in AVR  
programming in those days.

Morris
>

> Date: Mon, 23 Jun 2014 12:26:40 -0400
> From: Bob Bownes <bownes at gmail.com>
> To: Discussion of precise time and frequency measurement
> 	<time-nuts at febo.com>
> Subject: [time-nuts] microcontroller based IRIG generator
> Message-ID:
> 	<CACsYtUsmAdz_08+Z8sHEh=koPuCkko263ijh3HkA89yz=b0+Nw at mail.gmail.com>
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>
> I remember a few discussions over the last few years about building a
> microcontroller (PIC, Arduino, MPS430, whatever floats your boat) based
> IRIG generator. Did anyone ever get one working?
>
>
> Thanks!
> Bob
>