HamHUD II 18F252 Upgrade

Instructions on how to re-load firmare into the later-model HamHUD IIs with the PIC18F252 processor.

Steve Bragg KA9MVA's


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by Dale KG5LT
Last updated: Oct 05 2003 by KG5LT

(Dale, we seriously need to update this page. --KA9MVA 7/4/06)

Note!  If you're having trouble with the loader, see the Tutorial below.
NOTE!  If you have a new board fromMarch 2003, you will need to apply a 0.1uf cap between pins 19 and20 of the PIC socket.  I used a small SMT capacitor
(0805 size).  It fit nicely right on top of the pins on the bottomof the board.    If you use a leaded cap, be sure to makethe leads as small as possible.
This cures that flaky loading and running problems that Jason and Glennhave reported.

20 MHz Version

(see below for the 10 MHz version)

  1. Unzip the 27000a.zip file onto your PC in a directory of yourchoice.

  2. Make sure you have a cross-over cable between your PC and the HH2 board.

  3. Unzip the HH2Loader_Rel2_1.zip file in a directory of your choosing. I personally would keep it separate from the directory that your 27000a.zipfile was unzipped to.

  4. Fire up the HH2Loader_Rel2_1.exe file.  Open the Region menu and de-selectthe Code region.  You should only have the FRAM region selected forthis initial upgrade loading.

  5. Open the hex file: hamhud252.hex file.

  6. Customize the settings: callsign, symbol (see the symbol list further downthe customize grid) and perhaps your default lat/lon settings.  BTW,the symbol value near the top of the list is one (1) less than the symboltable index (symbol 1, a car, in the list would be a zero in your symbolvalue slot).

  7. After customizing your settings (these go into the FRAM), then save them.

  8. Now, click on the Loader Tab, but *don't* click the Load button, yet.

  9. Be sure your PC and HH2 board are serial cabled up.  Apply power tothe HH2 board while holding in on the WhizWheel knob.  You shouldsee the signon revision on line 3 and the words "Load FRAM!" on line 4and the word "Load" on line 1.  If you don't, you may have a problemwith that PIC.

  10. If you see the correct messages on the LCD of step 10, then click on theLoad Button on the HH2Loader program on your PC.  It should startloading if all is hooked up correctly.
Those should be the correct steps to follow for this 18F252 upgrade.

10 MHz (40 MHz internal) Version

The upgrade steps MUST be followed in order:
  1. Be sure you are currently using the 18F252 with the 20 MHz xtal.

  2. Get a copy of the hex file for the 10 MHz version: 27001b.zip. Unzip it in it's own subdirectory.

  3. Using the HH2Loader Release 2.1.  Select the new 10 MHz hex file.  (hamhud252.hex)

  4. Deselect the FRAM and have just the Code region checked for loading.

  5. Load the Code into your HH2.

  6. Once it is loaded, turn off your HH2.  DO NOT turn it on until AFTERthe next step.

  7. With power off, unsolder your 20 MHz xtal.  Install the 10 MHz xtal.

  8. Turn on the HH2.  It should come up with the latest firmware version.(2.7.001b)

Mini-Tutorial on the Loader

The way the HH2Loader on your PC and the HH2 internal loader work is thus:
  1. send low address byte to HH2.
  2. send high address byte to HH2.     { takes two bytesfor each address }
  3. get low address byte back.  If timeout, or mismatch of data, thendisplay error
  4. get high address byte back.   ditto ^
  5. send low byte of data for that address.
  6. if destined for FRAM, write to FRAM, read back from FRAM.
  7. get low byte of data back.  If timeout or mismatch of data, then displayerror.
It's in a constant handshaking mode.  send data, get data back andverify.

LED Behavior during load

When the low address byte is received, the HH2 loader turns on theRED led.

When the the last data byte is sent back as verification, the HH2 Loaderturns
the GREEN led on.

After a successful load, the GREEN led should stay lit.

While it is successfully loading data you should see a slightly orangecolor as
the RED/GREEN alternate.

Contact: Steve Bragg KA9MVA (email: steve _at_ hamhud.net)
Last Modified: July 4, 2006

Legal: The information in the HTML pages, schematic and source code are copyrighted © 1997-2006 by Steven D. Bragg, KA9MVA. License is granted to freely use, reproduce or modify this material, for non-commercial amateur radio purposes only. This information carries no warranty of any kind, including any implied warranty of fitness for any particular purpose. I am not liable for any damage to equipment or other property, or injury, or loss of life, attributable directly to, or related to, the construction or use of a HamHUD.