Editing Tandy Pocket Computer (section)

===Prog===
The Prog mode changed the input from a command line to a program editor. In this mode, BASIC programs could be entered one line at a time. Up and down arrow buttons were provided to scroll up and down through the program space. On most models, free calculations could not be entered in the Prog mode. Certain models, especially the Casio-derived ones, called this mode '''WRiTe mode.'''

On the Sharp models, there was only one [[line number]]ing space. In order for multiple programs to exist on the device, they had to be written in different ranges of line numbers. For example, it was common to insert one program starting with line 100, and another program starting at line 200, etc. Valid line numbers in most models were from 1 to 999. To prevent run-on execution, each program had to finish with the END command, unless run-on execution was desired. On Sharp-derived units, labels could be inserted into the program, usually single characters such that in Run mode, that program could be executed by depressing a special DEF key followed by the key of that character. This was equivalent to an explicit [[GOTO]] command to the first line number of that section of program, which was also a valid way to execute programs from Run mode.

In the Casio-derived models, the BASIC space was subdivided into segmented program spaces which could be numbered, cleared and executed manually, or could call each other.

Many of the devices included a special [[modifier key]] to expedite the entry of BASIC commands as well as scientific function names. The most common commands would each be associated with a key, and the full command could be entered by depressing the special modifier key, followed by the associated key for the command.

In some models, BASIC and other commands would be converted into one-character tokens (converted to strings upon display) instead of being stored as whole strings.