Normally the programs running on an ARM are running stand-alone and without
direct human input. However, during the bring up phase a programmer
may want to try different values. So a simplified replacement of the
normal BASIC INPUT has been added, called DEBUGIN.
INPUT is used to control the direction of one of the IO pins.
DEBUGIN has a limited edit capacity: it allows to erase characters using the backspace key. If a better user interface is needed, a custom input routine should be used.
DEBUGIN may also read a string from the control serial port.
DEBUGIN does NOT support SINGLE variables.
On the ARMweb, this command is available only on the debug USB port.
