The HamHUD II firmware has been sucessfully ported over to the PIC18F252. The 252 is pin-by-pin the same as the PIC16F876. There are two main advantages to the conversion over to the new 252, TWICE the code space and the ability to move up to a speed of 40MHz.
The final 876 firmware "j" was ported over to initially run at 20MHz. The code will eventually be converted over for 40MHz operation. In order to run the faster speed, the 20MHz crystal currently being used will be replaced with a 10MHz crystal. The 252 internally multiplys the 10MHz clocked signal by 4 to get 40MHz, pretty damn slick.
So far the firmware has proven to be very stable and already has many of the bugs from the "j" firmware fixed. A huge thanks goes to Dale Seaburg KG5LT for the port over. He has done about 99% of the work to make this happen. One problem has been found at it only has to do with the PCBs that were run off this past run. A re-design flaw allows noise to get into the PIC causing it to really act up. A fix has been devised by soldering in a 0.01uF capacitor between PIC pins 19 and 20 on the back side of the PCB. This has appeared to have fixed the problem 100%.
Keep checking back here for more updates or check www.hamhud.net for the latest news.
Interesting note about the picture above. I grew up and lived in Virginia Beach, Virginia for 17 years. I moved to Roanoke, Virginia 2 years ago. When I took this picture, A fellow ham (KE4AZL - Butch) that I had learned much from in Virginia Beach just happend to be getting a APRS message sent to him at the time I took it. The packet had been digipeated all the way from Virginia Beach to me, here in Roanoke :o)
The HamHUD - APRS heads up display was created by Steve Bragg KA9MVA. He, along with 15-20 other amazing hams created, developed and built the HamHUD. The HamHUD home page can be found at HamHUD.net.
The HamHUD has gone through many changes. It started as HamHUD I and contained a 2x16 LCD and was limited to it's functions. The HamHUD then moved onto the HamHUD II (current model). The heart of the unit is a 16F876 PIC programmed with firmware developed by Steve. A great source for cheap, high quality LCDs is Crystalfontz.
The HamHUD allows the TNC to talk to the radio and GPS all at the same time. It surpasses a "dumb tracker" due to the fact that the HamHUD allows the user to send canned messages, change icon, change status, change or edit the DigiPath and send simple commands to the TNC.
The picture above is a simulated view of the 4x20 LCD display built into the HamHUD.
Above is a picture of the Delorme Tripmate that sits on my dash just in front of the HH2. The HUD and GPS are held to the dash with velcro.
This is a picture of my HUD on my workbench. I have it in TNC bypass mode (hold down Beacon Now button when booting up). It shows NO GPS due to one is not attached. Some GPSs provide a sentence that will make the HUD show NO FIX when the GPS has not acheived sattelite lock. Unfortunatly, my GPS does not supply this sentence, so my HUD shows NO GPS untill the GPS has lock.
This is the right side of my HUD. It contains the power switch (toggle) and the power input jack (+12 VDC). I tried to make my HUD as universal as possible, such as this power jack. It will work with just about any off the shelf +12 VDC cigarette lighter cable with a standard barrel connector on the end. I use a RadioShack Cable that allowed me to put a right-angle connector on it (this cable can be seen in the HUD/GPS picture above).
Again wanting to stay universal, I made the TNC and GPS ports on the back of the HUD both DB-9 sockets. The TNC connector (left) uses the standard pin configuration, so an off the shelf DB-9 female to DB-25 male serial cable can be used to connect the KPC-3 to the HUD. As well as the GPS connector (right) uses a DB-9 socket and is pin-configured to accept a standard GPS to PC-link cable (I have a Garmin). The cable was originally made to connect the GPS to a DB-9 com port on a computer. I just took this and made it to my advantage.
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Here are some pictures from inside the HUD, kind of messy, but works. (Sorry for the crappy looking pictures, I'm still trying to get this new camera working to it's full)
Here is a picture of the backside of the DB-9s. I just used the ol' push through pin types. I like the solder pot types better, but if my memory serves me right, the shack was out of them at the time.
Below is a picture of the custom cable I made to go from the HUD to TNC. Well, actually, it's the DB-9 end. I used an off the shelf DB-9 to DB-25 for a long time but then made this custom cable to go with the dark interior of the truck. As well as everything else is black or dark colored. I soldered it so the cable would stick out to the right of the connector and keep it slim, since the cable has to jut to the right to go down to the TNC. I took the shielding braid and twisted it, then soldered it to the top of the connector. This kind of acts as a stress relief for the solder connections. Then I wrapped the back of the connector with electrical tape to protect it from the elements.
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Build APRS!!!
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