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Serial Ports Digital and Analog I/O
Special Purpose Digital and Analog I/O (A.I.T.P.)
The 4GMCU device is equipped with 3 digital input and 2 digital outputs that are physically
connected to the AITP Cpu, this oen can process them at higher rates which cannot be reached by
any Windows CE application.
Since the AITP Cpu can be on-board programmed, it’s possible to use them for many special purposes
that may be required in the future, requiring a customisation of the AITP program.
Anyway they can be used also in the standard release, reading and writing them with CommTax2
commands on the AITP serial port.
The main difference between this special I/O and the standard I/O is that the special ones can be
used as triggers, giving the possibility to monitor even the transitions of digital signals that have a
short and impulsive behaviour, which otherwise would be difficult or impossible to be detected by a
Windows application.
The ”PI” Commtax2 command gives the possibility to setup the triggers, specifying for each one of
the 3 special inputs if the trigger has to be enabled or not, if the trigger is on both transitions or only
on a selected one, and to select the Low to High transition or the High to Low one.
When the AITP Cpu detects the required transition, the ”SV” Commtax2 command is issued and the
customer application can easily detect the transition.
Special I/O status can also be read whenever desired with the ”GP” command, and the outputs can
be set with the ”WP” command. For further details, refer to the CommTax2 chapter.
Also 2 Analog Inputs are available to the AITP Cpu. Analog values can be read using ComTax2
commands.
Analog Input range is from 0 to 5.2 Volts, with 12 bits of DAC resolution. (0 to 4092) Analog Input 1 is
connected to Digital Input 1, analog Input 2 is connected to Digital Input 2.
Power ON/OFF using special input 3
Special Input 3 can be set to turn ON and/or OFF the MCU. This feature can be enabled using the Aitp
Setup program for PC, where is possible to decide after how many seconds from low to high
transition the MCU has to be powered ON, and after how many seconds from high to low transition
the MCU has to be powered off. This ON/OFF timers are independent and can be singularly disabled.
