If anyone has this book, could you please help me with experiment 47; Producing Random #'s. Have you gotten this thing to work? Is the code even valid, or what? I've set this up many times, and yet it still fails to work. I know how to use LCD's, but maybe this is just another of Myke's (the author) typos.

Thanks for your consideration,
mpuvdd

 

Copy your code and paste it here so people can compare it to their copy in the book.

 

I got this code from http://pic18fusb.online.fr/PicKit2, only because it is not shown in the book.

#include <pic.h>
/* cRandom.c - Display a Random Number Each Time a Button is Pressed

This Program Initializes Hitachi 44780 Based LCD in 4 Bit Mode
and then writes a simple string to it. The simulator was used
to time delay values.

LCD Write Information can be found at http://www.myke.com

RA5 - Button Input
RC3:RC0 - LCD I/O D74 (Pins 14:11)
RC4 - LCD E Clocking Pin
RC5 - LCD R/S Pin

myke predko
04.11.08

*/

__CONFIG(INTIO & WDTDIS & PWRTEN & MCLRDIS & UNPROTECT \
& UNPROTECT & BORDIS & IESODIS & FCMDIS);

// 1234567890123456
const char TopMessage[] = " Random Number: ";
const char BotMessage[] = " "; // Number Follows

#define Button RA5 // Define Button Input
#define E RC4 // Define the LCD Control Pins
#define RS RC5

const int Twentyms = 1250; // Declare a Constant for 20 ms Delay
const int Fivems = 300;
const int TwoHundredus = 10;

LCDWrite(int LCDData, int RSValue)
{
int i, j;

PORTC = (LCDData >> 4) & 0x0F; // Get High 4 Bits for Output
RS = RSValue;
E = 1; E = 0; // Toggle the High 4 Bits Out

PORTC = LCDData & 0x0F; // Get Low 4 Bits for Output
RS = RSValue;
E = 1; E = 0; // Toggle the Low 4 Bits Out

if ((0 == (LCDData & 0xFC)) && (0 == RSValue))
j = Fivems; // Set Delay Interval
else
j = TwoHundredus;

for (i = 0; i < j; i++); // Delay for Character

} // End LCDWrite

main()
{
int i, j;

PORTC = 0; // Start with Everything Low
CMCON0 = 7; // Turn off Comparators
ANSEL = 0; // Turn off ADC
TRISC = 0; // All of PORTC are Outputs

OPTION = 0b01001111; // Run TMR0 From PIC MCU Clock

// Initialize LCD according to the Web Page
j = Twentyms;
for (i = 0; i < j; i++); // Wait for LCD to Power Up

PORTC = 3; // Start Initialization Process
E = 1; E = 0; // Send Reset Command
j = Fivems;
for (i = 0; i < j; i++);

E = 1; E = 0; // Repeat Reset Command
j = TwoHundredus;
for (i = 0; i < j; i++);

E = 1; E = 0; // Repeat Reset Command Third Time
j = TwoHundredus;
for (i = 0; i < j; i++);

PORTC = 2; // Initialize LCD 4 Bit Mode
E = 1; E = 0;
j = TwoHundredus;
for (i = 0; i < j; i++);

LCDWrite(0b00101000, 0); // LCD is 4 Bit I/F, 2 Line

LCDWrite(0b00000001, 0); // Clear LCD

LCDWrite(0b00000110, 0); // Move Cursor After Each Character

LCDWrite(0b00001110, 0); // Turn On LCD and Enable Cursor

for (i = 0; TopMessage != 0; i++)
LCDWrite(TopMessage, 1);

while(1 == 1) // Loop Around Waiting for Button
{
i = 0; // Wait 20 ms for Button Up
while (i < Twentyms)
if (0 == Button) // Button Down/Start over
i = 0;
else // Button Up/Increment Count
i = i + 1;
NOP();
i = 0; // Wait 20 ms for Button Down
while (i < Twentyms)
if (1 == Button) // Button Up/Start over
i = 0;
else // Button Down/Increment Count
i = i + 1;

LCDWrite(0b11000000, 0);// Move Cursor to the Second Line

for (i = 0; BotMessage != 0; i++)
LCDWrite(BotMessage, 1);

i = TMR0; // Save TMR0 Value
if (i > 100) // Convert TMR0 Value to Decimal
LCDWrite((i / 100) + '0', 1);
else // No Hundreds to Display
LCDWrite(' ', 1);
if (i > 10)
{
i = i % 100; // Not Greater than 10
LCDWrite((i / 10) + '0', 1);
}
else
LCDWrite(' ', 1);
LCDWrite((i % 10) + '0', 1);

} // elihw
} // End cRandom