This text is largely based on the original "qrpkeyer.txt"
written by Wolfgang (Wolf) Buescher, DL4YHF.

This version of the keyer offers the following features:

- it is aimed specifically at the PIC 16F628A microcontroller
  and unlike the orginal QRP Keyer code no attempt is made
  to retain compatibility with older microcontrollers, such as
  PIC16F84 and PIC16F628 . The program source code still contain
  references to those older PICs but they will be removed as this
  version of the keyer evolves.
- it is meant to be used with the Four State QRP Group Keyer Kit
  circuit v3.0, which schematic at the time of this writing can be
  found at http://www.wa0itp.com/aa0zzkeyerschematicv3.pdf .
- variable CW speed, adjustable via poti from about 5 to 50 WPM .
- two message memories (63 and 55 characters respectively), each
  controlled by a pushbutton.
- command mode only required for setup and more complex features.
- special modes like "endless" calling loop and automatic contest
  number generation.
- power-supply between 2.4 and 5 Vdc.
- very low power consumption: 50 microamperes at 2.4 V supply when active,
  less than 1 microampere in standby mode (which is enterd automatically)
- dash/dot-memory can be turned on and off (I guess that's "Iambic mode A"
  and "B")
- controller is clocked by a built-in RC-oscillator
  with only 50kHz clock frequency.
- passive piezo speaker can be connected as sidetone.


Instructions on how to compile the code on Linux platforms are included in
the prologue of "qrpkeyer4.asm". The code should compile just as fine on
MS-Windows boxes, by using PIC development suites such as MPLab and the
many other available.

I'd also like to retain Wolf's original closing sentence from "qrpkeyer.txt" :

  Good luck and have fun with this project. Life is long enough for QRP.
  73's from DL4YHF (Wolfgang).