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Gearing up for End of Year Project of the Month Contest. Donations Welcome


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Well, if anything, I started on my project, already have the moon phase math mostly coded (simple, whole number math, modulo via subtraction, for performance)(a more precise version would include floats, because fix point math would make my head hurt)

 

And I have a full writeup of how the Maxim DS1337 i2c rtc works and most of the maxim rtcs have the same basic rtc/alarm/control setup, so hey, new library for use (which is weird, noone has used a hardware rtc on this board as far as some searching goes. Some software rtc setups, but the few projects that used like a maxim/dallas rtc never actually posted code)

 

So yea, I plan on joining in.

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Well, if anything, I started on my project, already have the moon phase math mostly coded (simple, whole number math, modulo via subtraction, for performance)(a more precise version would include floats, because fix point math would make my head hurt)

 

And I have a full writeup of how the Maxim DS1337 i2c rtc works and most of the maxim rtcs have the same basic rtc/alarm/control setup, so hey, new library for use (which is weird, noone has used a hardware rtc on this board as far as some searching goes. Some software rtc setups, but the few projects that used like a maxim/dallas rtc never actually posted code)

 

So yea, I plan on joining in.

Sounds cool. I tried a hardware RTC on my clock but got frustrated and went with software - I'd love to see that code.

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Sounds cool. I tried a hardware RTC on my clock but got frustrated and went with software - I'd love to see that code.

 

i had a write up to do bit-bang i2c w/ a PCF8563 if u anyone is interested. i planned to use a dallas RTC and found out that the common ones 1307 etc are 5v and quite expensive (back then). the PCF8563 cost around 50cent a piece (buy 10).

 

http://www.simpleavr.com/msp430-projects/rtc-clock

 

code also do alarm / day of week / calendar and such.

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Sounds cool. I tried a hardware RTC on my clock but got frustrated and went with software - I'd love to see that code.

 

As soon as I finish writing it up :grin:

 

i had a write up to do bit-bang i2c w/ a PCF8563 if u anyone is interested. i planned to use a dallas RTC and found out that the common ones 1307 etc are 5v and quite expensive (back then). the PCF8563 cost around 50cent a piece (buy 10).

 

http://www.simpleavr.com/msp430-projects/rtc-clock

 

code also do alarm / day of week / calendar and such.

 

I wasn't able to find your project in the search, even though I remember it a few years back now.

 

And yea, the maxim rtcs are expensive. I was able to sample a ds1337C, which has a built in 32k crystal oscillator, and just priced it out, 5 bucks in <25 quantity. But no need for sourcing the crystal or caps which is nice.

Unfortunately, I was a) banned from maxim, and B) chose the wrong one cause I didn't pay attention.

The ds1337 doesn't have battery backup feature.

 

The 3v compatible version of the ds1307 is the ds1338, with battery backup and 2 alarms (one pin). Does 1.8v to 5v (they have three different part numbers, -18 (1.8 to 5v, 1.8typ) -3 (2.7 to 5v, 3v typ) and -33 (3v to 5v, 3.3v typ) which is weird).

Priced the same as the 1307 from what I can see (~3 in single qty, c version is ~5)

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As soon as I finish writing it up :grin:

 

 

I wasn't able to find your project in the search, even though I remember it a few years back now.

 

And yea, the maxim rtcs are expensive. I was able to sample a ds1337C, which has a built in 32k crystal oscillator, and just priced it out, 5 bucks in <25 quantity. But no need for sourcing the crystal or caps which is nice.

Unfortunately, I was a) banned from maxim, and B) chose the wrong one cause I didn't pay attention.

The ds1337 doesn't have battery backup feature.

 

The 3v compatible version of the ds1307 is the ds1338, with battery backup and 2 alarms (one pin). Does 1.8v to 5v (they have three different part numbers, -18 (1.8 to 5v, 1.8typ) -3 (2.7 to 5v, 3v typ) and -33 (3v to 5v, 3.3v typ) which is weird).

Priced the same as the 1307 from what I can see (~3 in single qty, c version is ~5)

 

when i turn my 3p4w clock and adopt a rtc chip, i didn't post it in a new thread and it wasn't very noticeable.

 

for rtc chips, if u search ebay for reasonable price rtc chips, it's just the 1307 or the pcf8563. for 3v i went for the pcf8563, there are less source code examples but it's the same principle and not too hard to work w/ once i get the timing right.

 

for the 1338 or dallas 3v rtc's, i figure i had to order from a formal supplier and the shipping always kill the deal for small quantities. for similar price i got 10 pcf8563s. anyway the pcf8563 is a great litte chip and i still have the clock running at my office desk.

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