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Bots / The Ultimate Palm Robot/ Mukhar & Johnson / 222880-6 / Chapter 7

164 The Ultimate Palm Robot

Command Description
form btn x,y, width, Creates a form button at the given x,y coordinate and with the
height, label$, 1 given width and height. The label of the button is given by the
string parameter.
fn formbtn( ) Returns the key code of the last form button that was tapped.
draw -1 Clears the display.
draw t$, x,y Draws text t$ at given screen position.
fn wait(n) Delays for n seconds.
Table 7-1
Some of the More Common or Useful HotPaw Functions (continued)

Creating and drawing forms is fun and leads to strong minds and bodies,
but to work with the PPRK, we need to be able to communicate over the serial
port. Some of the commands for sending and receiving data over the serial
port are shown in Table 7-2.

Command Description
open “com1:”,9600 as #5 Opens the serial port. Note that you must always use the command
as shown. COM1 is the only valid serial port, 9600 baud is the
speed that the Pontech SV203 controller is using, and only
descriptor #5 is valid for serial port communication.
print #5, a$ Prints the string a$ to the serial port.
get$(#5, n) Returns a string up to n bytes long.
input #5, a$ Waits for one line of text.
close #5 Closes serial port.
fn serial(5) Returns the number of bytes to be read from descriptor #5.
Table 7-2
HotPaw Basic Commands for Using the Serial Port of the Palm

PPRK Programming with HotPaw Basic
Now that we’ve seen a simple application using HotPaw Basic and some of the
HotPaw Basic commands and functions, let’s actually write some code for the
PPRK. We’ll first discuss what the program is intended to do, and then show
the code.

The Simple Jig Program

This program will be simple in concept, but as you will see, it does involve a
bit more code than we saw earlier. The program will run in a loop. Within the

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