The on screen keyboards in TTerm for iPad offer three different shift key functions.
Single tapping the Shift key on the on-screen keyboard alters all the keys to their shifted state for the next keypress, after which they revert to their normal state. This follows the normal operation of iPad default keyboards.
Double tap the Shift key to lock the entire keyboard to it's shifted state including numbers 0-9 and letters a-z. Any subsequent key taps will be shifted and the lock will be removed only when tapping the shift key a second time.
Triple tap a Shift key to lock only the letter (a-z) keys to their shifted states. This is the equivalent to a CAPS LOCK. Any subsequent key taps on these keys will be in shifted and the lock will be removed only when tapping the shift key again.
Triple tap caps lock only applies to TTerm for iPad version 1.1.0 and above
Earlier versions of TTerm for iPad supported the single and double tap modes only..
You can also lock (single and double tap) CONTROL keys, ALT keys as well as other modifiers unique to certain emulation keyboards, for example the COMMAND key on the Data General keyboard.