KEYS

Description

KEYS is a pseudo variable which can be used to read the state of various digital input lines. KEYS is read-only. Any attempt to write KEYS will be rejected by the compiler. Each bit of KEYS belongs to one input line. Currently, these bits are defined:

BIT 0 Port P1.17 on the LPC2366. This pin is used for the external key. This signal is inverted by the firmware: Pulling the key pin to ground causes the KEYS command to issue a one.

BIT 1 The CTS input of the RS232 interface which is P2.2 on the LPC2366, if RS232 flow control is not set to RTS/CTS. Otherwise this bit is always 0.

BIT 2 The DSR input of the RS232 interface which is P2.4 on the LPC2366.

BIT 3 The DCD input of the RS232 interface which is P2.3 on the LPC2366

New since version 3.48: The following inputs can also be read with the KEYS pseudo variable. But this only works if that pin is configured as input. Please see the PORT command: click

BIT4 Pin 2 on the base module

BIT5 Pin 3 on the base module

BIT6 Pin 4 on the base module

BIT7 Pin 5 on the base module

BIT8 Pin 6 on the base module

BIT9 Pin 7 on the base module

BIT10 Pin 8 on the base module

BIT11 Pin 9 on the base module

BIT12 Pin 10 on the base module

BIT13 Pin 11 on the base module

BIT14 Pin 12 on the base module

BIT15 Pin 15 on the base module

BIT16 Pin 16 on the base module

Example

This program reads the external key in an endless loop and shows if it is pressed:

outmode -2
do
   if KEYS and 1 then 
      print "pressed"
      while KEYS and 1
      wend
   end if
loop

Remarks

To extract single bits, you can use the AND operator.