is there a tutorial for the ICE CLOCK and ULTIMATE GPS
Moderators: adafruit_support_bill, adafruit

is there a tutorial for the ICE CLOCK and ULTIMATE GPS

by khoyt on Wed Feb 06, 2013 2:31 pm

Has anyone published the steps for hooking up the ultimate gps to the ice clock?

I'd much rather follow some nice pictures than risk ruining both!!

Any help would be appreciated :-)
khoyt
 
Posts: 4
Joined: Thu Jan 07, 2010 12:30 am

Re: is there a tutorial for the ICE CLOCK and ULTIMATE GPS

by jarchie on Thu Feb 07, 2013 5:06 pm

I don't think the default Adafruit firmware supports this out-of-the-box, so you need an AVR programmer. If you don't have experience with AVR programming it would good to have an extra ATmega128 or (preferably) an ATmega328p lying around.

If you have a programmer and ATmega328p, I am willing to write some instructions with photos. The GPS hack is fairly straightforward.
--John <www.jarchie.com/email>
jarchie
 
Posts: 419
Joined: Sun Jun 24, 2012 2:16 pm
Location: Santa Cruz, California, United States

Re: is there a tutorial for the ICE CLOCK and ULTIMATE GPS

by khoyt on Thu Feb 07, 2013 7:49 pm

I have updated the firmware for the clock, been a while, but giving it another shot is part of the fun!

No rush... don't even have the GPS yet...
khoyt
 
Posts: 4
Joined: Thu Jan 07, 2010 12:30 am

Re: is there a tutorial for the ICE CLOCK and ULTIMATE GPS

by jarchie on Tue Mar 12, 2013 9:31 pm

Installing the Ultimate GPS is not too different from the procedure described in the Adafruit Learning System, so that documentation should still be helpful. But here is a description of the process for the Ultimate GPS breakout.

On the software side, you'll need to choose a firmware, and the required hacking/configuration will depend on the particular firmware you choose. I am aware of three firmware projects which support GPS.

The Adafruit GPS firmware will run on the ATMEGA168V that comes with the Ice Tube Clock but the code requires modification to compile under recent versions of GCC. Also the Ultimate GPS runs at 9600 baud, but the Adafruit code expects to connect at 4800 baud. Therefore, the line in iv.c that reads "uart_init(BRRL_4800);" must be changed to "uart_init(BRRL_9600);".

Two alternative firmwares support the Ultimate GPS Breakout and compile without modification, but both require an ATMEGA328P-PU. An ATMEGA328P-PU costs around $10 from Digi-Key or Mouser ($3 + $7 shipping). In my opinion, the additional features provided by these firmwares far outweigh the cost and inconvenience of replacing the microcontroller.

The first of these alternatives is my xmas-icetube firmware, which supports the Ultimate GPS baud rate by default. Follow the instructions in the README file and be sure to uncomment the GPS_TIMEKEEPING macro in config.h. Please let me know if you have any difficulty. (Note that the xmas-icetube firmware is so named because I received the Ice Tube Clock as a Christmas gift. The firmware works perfectly well at other times of the year.)

The second alternative is William Phelps' firmware, which also supports the Ultimate GPS out-of-the-box. If I remember correctly, the GPS option must must be toggled from "gps off" to "gps on96". William is a regular on these forms and would probably be willing to help if you have difficulty.

On the hardware side, there are many ways to install the Ultimate GPS, but the following describes my method.

The Ultimate GPS is small enough to fit inside the acrylic case, so I chose that option. To install the module, I soldered wires to the GPS's VIN, GND, and TX pins and glued the assembly on the upper left corner of the rear acrylic piece. For glue, I like marine silicon which is overkill, but always seems to work well.
Image

To run the wires, I cut a small notch in the clock's PCB board.
Image

To connect the GPS, I used the ground and power directly from the voltage regulator, and the GPS's TX line was connected to the ATMEGA's RX pin. Drawing GPS power before D2, means that GPS power is cut when the clock loses external power, which saves the clock's internal battery. The battery is still useful because the GPS needs a minute to acquire satellites after external power is restored; without the battery backup, time will be incorrect immediately after a power outage. And on the xmas-icetube firmware, enabled alarms will sound during power outages if the backup battery is good. (On the photo below, ignore the red and yellow wires which do not loop around the PCB; they are for the extended battery hack.)
Image

The last steps were assembling the case and setting the timezone. On my firmware the timezone does not incorporate daylight saving time and is specified relative to GMT/UTC under "cfg regn"/"set zone" in the menus. So the zone would be "-05h 00m" for New York and "00h 00m" for Lon-don. Daylight savings time may be specified under "cfg regn"/"set dst" and has four settings: "dst on", "dst off", "dst usa", and "dst eu". The first two provide manual DST control; the last two automatically toggle DST in accordance with US or EU rules.
Image

Hope that helps. Good luck and happy hacking!

(edited post; originally posted on 08 Feb 2013 02:43)
Last edited by jarchie on Mon Oct 28, 2013 5:35 pm, edited 1 time in total.
--John <www.jarchie.com/email>
jarchie
 
Posts: 419
Joined: Sun Jun 24, 2012 2:16 pm
Location: Santa Cruz, California, United States

Re: is there a tutorial for the ICE CLOCK and ULTIMATE GPS

by srdevil on Sat Aug 17, 2013 6:37 am

I've reading this post abouth the "Ultimate GPS Breakout", but I was wondering why u didn't fit the GPS under the main PCB. It would be less visable, the only negative point might be that it's not in the case anymore.

If I measure the bottom of my Acryle case it should be 26 [mm] wide and according to the specs of the GPS it says:
•Dimensions (not including coin cell or holder): 25.5mm x 35mm x 6.5mm / 1.0" x


If u glue the PCB under the acryle bottom and keep the wires long enough it should be possible to remove the main PCB from the acryle bottom if u need to edit the bottom of the board. Also I suppose that u didn't install the coincell/holder?
srdevil
 
Posts: 23
Joined: Mon Jul 22, 2013 5:20 pm

Re: is there a tutorial for the ICE CLOCK and ULTIMATE GPS

by jarchie on Sat Aug 17, 2013 5:18 pm

srdevil wrote:I've reading this post abouth the "Ultimate GPS Breakout", but I was wondering why u didn't fit the GPS under the main PCB. It would be less visable, the only negative point might be that it's not in the case anymore.

I just wanted to keep the GPS inside the case. Mounting it under the case might work also, but I never tested that configuration. Reception might not be as good when mounting the GPS under the PCB due to interference from the copper traces and electronic components. Reception might also suffer if you mount the unit upside down.

srdevil wrote:Also I suppose that u didn't install the coincell/holder?

Correct.
--John <www.jarchie.com/email>
jarchie
 
Posts: 419
Joined: Sun Jun 24, 2012 2:16 pm
Location: Santa Cruz, California, United States

Re: is there a tutorial for the ICE CLOCK and ULTIMATE GPS

by jarchie on Mon Jan 20, 2014 5:44 pm

jarchie wrote:Mounting it under the case might work also, but I never tested that configuration. Reception might not be as good when mounting the GPS under the PCB due to interference from the copper traces and electronic components. Reception might also suffer if you mount the unit upside down.

It looks like my concerns were unjustified here. Forum user rcb mounted the Ultimate GPS upside-down under the case and that configuration seems to work rather well.
--John <www.jarchie.com/email>
jarchie
 
Posts: 419
Joined: Sun Jun 24, 2012 2:16 pm
Location: Santa Cruz, California, United States