Introduction   (last modification on 28th November 2007)

The CWKtiny is a microprocessor module with a built in AT keyboard interface, usable as a "Morse type writer". It's undependend from a PC, easy to operate and suitable for portable activities. It works within a voltage range from 7 up to 15 Volts. The total power consumption mainly depends on the keyboard with a big influence of its LEDs (for example 12mA all LEDs off, 50mA all LEDs on). Avoid to connect "ancient" keyboards to the CWKtiny. Possibly they consume up to 200 mA or do not work at all. The same might be valid for special function keyboards (e.g. multi-media). In case you are not sure, try it out or measure the current. A suitable adapter also allows attachement of keyboards with USB or older DIN connector.

The heart of the module is an ATMEL microprocessor AT89S52 which converts the scan code of the keyboard into CW code. Several standard QSO textes and a few setup values can be stored in the 24C08 EEPROM which is connected via I²C bus to the processor. To prevent RF from coming in on the keyboard's data and clock lines coils L1,L2,L3 are inserted. If the keyboard itself produces RF emission noise in your radio receiver click a ferrite bead on the keyboard cable. But most of the keyboards manufactured in the last few years do not cause such a lot of radiation.
Several processor output pins are lead to connectors in order to use them in future software versions. The connectors are not extend of delivery as they are mainly needed for QRSS operation only. The CWKtiny is available as a ready-built module or as a kit. Look at "Scheme/PCB"  from where you can download all documents needed for homebrewing.

Features

- PS/2 keyboard interface
- Typing and CW speed are undependent from each other (64 characters type ahead buffer)
- PTT output (FET BS107, open drain)
- 8 standard message memories (non volatile)
- 50 characters quick memory (volatile) for temporary storing of textes (i.e. for the call of the QSO partner)
- quick memory is combinable with one of the standard text memories
- ENTER toggles between two "on-the-fly" changable speeds
- Speed adjustment coarse ("V's" are transmitted)
- Speed adjustment fine (changes speed immediately, effective during running CW transmission)
- 7 different Morse practise modes
- individual adjusting of Dit/Dah weighting and spacing as well as character spacing
- additional pause between words by "SPACE" key
- some "ALT-letter" combinations to send telegraphy prosigns like AR, SK etc.
- embedded commands in messages
- automatically generated contest number (number "zero" choosable as T or 0)
- permanent PTT for SWR tuning
- special key to cancel CW transmission, CW practicing mode, memory input or other functions immediately
- keyboard LEDs signalize memory overflow, false key strokes or the current program status
- error correction with "backspace"
- cylic repetition of memory textes (CQ loops), adjustable from 0 to 240 sec.
- automatic beacon restart after power-on
- use of control codes in memory textes to influence processor outputs, to generate time loops or permanent keying of the PTT line
- a special cotrol code for repeating a memory text block multiple times
- supporting the QRPP modes QRSS3,5 ...120 DFCW, FSKCW, FATCW, SLANT, Triangle-CW, SLOWHELL and SQUELL
- Multilingual keyboard layout (english, french, belgian, dutch, german ... islandic)
- Squeeze paddle support for iambic and ultimatic mode.
- Current keyer status as CW output