Experimenter’s Module
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5.2 Programming the Digital I/O Ports
Use the sfCOMDIGOUT PSOS command and the related Saphira convenience
command to manage the various digital output ports. They are described in detail in the
previous chapter. (PAI and P-LOGO support similar commands, too.)
For example, to turn the right LED on, use:
sfRobotCom2Bytes(sfCOMDIGOUT, sfRIGHTLEDBIT,
sfRIGHTLEDBIT)
Or alternatively, specify the state of an LED:
void sfGripperSetLed(int which, int state)
for which=sfLEFT or sfRIGHT, and state=sfON or sfOFF.
5.3 Programming the A/D Ports
The eight analog-to-digital (A/D) ports on the Experimenter’s Module (AN0-7) are
multiplexed from a single A/D port on the Pioneer 1 microcontroller. Hence, only one
port may be read at a time, although all eight ports may connect to individual sources.
Each AN port accepts a 0-5VDC analog input and outputs a proportionally related,
single byte value 0-255. Use the digital output ports OD5-7 to address which port PSOS
will read and return as the A/D value in the Server Information Packet (section 3.2, PSOS
Server Information Packet).
For example, the following Saphira command addresses the AN4 port by masking the
OD5-7 ports, setting OD7, and resetting OD5 and OD6: (remaining output ports remain
untouched:
sfRobotCom2Bytes(sfCOMDIGOUT, 0xE0, 0x80)
5.4 Programming the Speaker
The latest PSOS implements a new command called SAY, which plays a sequence of
up to 20 notes through the Experimenter’s Module speaker. Now your Pioneer will be
humming a different tune!
The SAY command (number 15) has two arguments: a string up to 40 bytes long, and
the integer number of actual bytes in the string:
sfRobotComStrn(sfCOMSAY, str, n)
The string is comprised of duration and tone pairs; the duration byte is the number of
20 millisecond increments the following tone value half-cycle times—in 150
microsecond increments—should be played through the speaker.
For example, to play two short, high beeps using the Saphira equivalent command:
void sfPlayToneString ("\010\002\010\000\010\002", 6)
