GPS HAT usable on original model B Pi?

[stan_qaz]

I have an old 2011 model B Pi that I was thinking of turning into a GPS based NTP server once my Pi B v2 arrives but while looking at the options to add the GPS to it I saw this HAT and really liked the cleaner look I'd get using it.

Raspberry Pi Model B 512MB RAM
PRODUCT ID: 998
https://www.adafruit.com/products/998

Adafruit Ultimate GPS HAT for Raspberry Pi A+/B+/Pi 2 - Mini Kit
PRODUCT ID: 2324
http://www.adafruit.com/products/2324

Looking at the pins used on the HAT above and available on my old Pi it looks like it might be usable If I trimmed a few pins off the header before I soldered it down. Is this a possibility or do I need to use the old method of buying the GPS breakout board below and a proto-board to connect it up?

Adafruit Ultimate GPS Breakout - 66 channel w/10 Hz updates - Version 3
PRODUCT ID: 746
https://www.adafruit.com/product/746

I don't see any proto boards for my old Pi, would this one work if I cut the header down to remove the additional pins?

Adafruit Perma-Proto HAT for Pi Mini Kit - No EEPROM
PRODUCT ID: 2310
https://www.adafruit.com/products/2310


Or would I be better off discarding the old Pi B and just getting a new one?

[adafruit_support_mike]

Trimming the header down to fit an older RasPi will work, but you'll only need to remove the parts that would be blocked by other hardware on the RasPi. Leaving header rows that don't connect to anything is fine.

The TX and RX pins should be the same on the older-model B as on newer versions, so I'd expect the GPS module to work and play nicely with the older RasPi.

[stan_qaz]

Thanks for the good news, off to do some shopping.

[stan_qaz]

An update. I got my GPS hat and was looking at it and my old original Pi B and realized the only thing blocking the header was the composite video out jack. That only has three fair sized pins holding it in so I removed it and didn't have to trim the hat's connector. That may prove handy later if I move the hat to a Pi 2 and use the prototype area.

The GPS hat is working on the original Pi B with no issues, I'm in the process of re-configuring it to provide me with an NTP time server for my LAN.

Thanks again for your assistance.

[adafruit_support_mike]

An update. I got my GPS hat and was looking at it and my old original Pi B and realized the only thing blocking the header was the composite video out jack. That only has three fair sized pins holding it in so I removed it and didn't have to trim the hat's connector.

That would do the job too.

Glad to hear you've got it working. There's another thread here in the RasPi forum where people are getting NTP servers running: http://forums.adafruit.com/viewtopic.php?f=50&t=70133 You may find some useful information there.

[stan_qaz]

I saw that topic which is what got me to buy the GPS hat, they helped me over a couple rough spots there too.

I think that it would be great to have the information there condensed into a single how-to and included into the learn area you offer. Is there a submission process to get things added there or do you accept contributions from folks like me?

https://learn.adafruit.com/adafruit-ult ... spberry-pi

This Pi GPS hat is really a fantastic deal for folks needing a good clock compared to every other GPS based clock I've seen. At around $100 for everything you need to set it up blows away the competition. My timing system for my LAN hasn't fully stabilized yet, errors are still trending down as the NTP system stabilizes. My timing errors have dropped from around 10 ms using my ISP's GPS based NTP server over the Internet to 0.5 ms using my Pi and the GPS hat when monitoring on a couple clients that offer charting and statistics.

I'd bet you could make a tidy profit offering a Pi system package, your hat, the antenna bits and a SD card pre-configured as an NTP server to folks that need one but can't afford the $1000 plus others are charging for an NTP GPS time server.

[stan_qaz]

Removing the video header was rather simple and allowed the GPS hat to fit on the old mod B Pi without interfering with anything so that went well. I did worry a bit about accidental pressure on the GPS hat causing contact between the tall capacitor near the HDMI jack so I added a bit of stick-on insulation there to avoid future accidents.

The original mod B pi is happy in the Adafruit Pi Box - Enclosure for Raspberry Pi Model A or B after a bit of tweaking. Two things didn't fit, first the GPS chip is too tall and contacts the case lid and second the hat board is a bit too long on the power jack end for the case to snap closed.

First, I trimmed a small hole in the top of the case for the chip to fit through, doing that again I'd not try to make it square but just drill a round hole which would look better and be easier to fit a cap over.

Second, I cut two slots in the case end above the power jack that allowed the hat to slip into them and the end to snap on.

I also drilled a hole to mount the antenna connector on the USB end of the case as there was more room there.

Case: https://www.adafruit.com/products/859

GPS hat: http://www.adafruit.com/products/2324

Case showing hole in top and slots in end.

DSCN1265_v1.jpeg (130.8 KiB) Viewed 346 times

[adafruit_support_mike]

Nice! Thanks for posting!