Morse Input
elyas-bhy has been working on the implementation of a Morse input method for the Tecla Access app as part of the Google Summer of Code. This page compiles his work and will eventually document the use of the feature.
The initial design of the Morse input UI is mainly focused on helping unexperimented users discover and learn all about the Morse code, as well as providing an optimal solution for more experienced users. Users are provided with a HUD to help them look-up the Morse sequence for their desired character, as well as an indicator on the space/end-of-character key, to keep track of the current sequence and its matched character.
To switch between standard input and Morse input, users must go to the settings screen and simply toggle on/off the Morse preference. Users are provided with several options in order to configure Morse input to their taste:
- Enable Morse input.
- Show/hide Morse HUD.
- Morse input method: triple-key, double-key or single-key mode.
- Configure Morse time unit (only in double-key and single-key modes).
- Configure on-hold repeat frequency (only in triple-key mode).
Currently, the user may choose to operate the Morse keyboard using one of the following methods:
- Fullscreen switch mode.
- Triple-key mode: dit, dah and space/end-of-character keys are operated by 3 different keys. This mode also supports an "on-hold repeat" feature (switch only), and the repeat frequency is configurable.
- Double-key mode: dit and dah are operated by 2 different keys, and the end-of-character event automatically takes place after 3 Morse time units (the duration of a unit is configurable).
- Single-key mode: this method is identical to the standard Morse method (recommended for experienced users only). More information about the timing here: http://en.wikipedia.org/wiki/Morse_code#Representation.2C_timing_and_speeds
Note that all these modes are accessible to touchscreen users as well as switch users. The following is a preview of the single-key UI, as it is slightly different from the other modes:
Upon activating the HUD preference, users will be provided with a Morse table above their keyboard. The HUD has 3 different states, based on the current Morse sequence:
- If the current sequence is empty, the HUD will show the most common characters, as well as the command actions (enter, delete, space, etc...).
- If the current sequence starts with a dit, the HUD will show hints of all the characters that start with a dit.
- Likewise, if the current sequence starts with a dah, the HUD will show hints of all the characters that start with a dah.
Experienced users may choose to toggle off the HUD from the settings screen.
By checking the "Sound on keypress" preference, users will be provided with an audio feedback that matches the duration of a dit/dah press, whether using the soft keyboard, or switch input.
In order to enhance the experience, users can configure their switch commands. They can choose these commands from a predefined list of actions. Note that when using the triple-key mode, you can assign specific Morse commands to your switches. These commands are enabled only when the Morse keyboard is shown.
Users can choose to display a cheat sheet anytime simply by a long-press on the space/endof-character key (currently available to touchscreen users only).
