Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronic Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

Help on SPI IO Expander MSP23S17

Status
Not open for further replies.

worksmart

Newbie level 5
Joined
Dec 13, 2004
Messages
10
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
78
aduc841.h

Hi all,

I stuck up with intrfacing SPI IO Expander MSP23S17 with ADUc841 microcontroller SPI port. IO expander is not responding. My K*e*i*l code I have gven below.
Can anybody help me.
Regards
Worksmart

//***************************************

#include<stdio.h>
#include <intrins.h>
#include <ADUC841.H>
sbit spi_cs = P3^4;
void write_spi(unsigned char c);
void delay(void);
void main(void)
{
unsigned int i=0;
unsigned char c=0;
SPICON=0x33;

spi_cs = 0;
delay();
write_spi(0x40);
write_spi(0x05);
write_spi(0xB0);
spi_cs = 1;
delay();
spi_cs = 0;
delay();
write_spi(0x40);
write_spi(0x0);
write_spi(0x0);
spi_cs = 1;
delay();
spi_cs = 0;
delay();
spi_cs = 0;
delay();
write_spi(0x40);
write_spi(0x09);
write_spi(0x0F);
spi_cs = 1;
delay();
while (1);
{
spi_cs = 0;
spi_cs = 1;
i=0;
while(--i);
}
}

void write_spi(unsigned char c)
{
//spi_cs = 0;
ISPI = 0;
SPIDAT = c; //write mode
while(!ISPI);
_nop_();
_nop_();
_nop_();
//spi_cs = 1;
}

void delay(void)
{
unsigned int i=100;
while(--i);
}

//*******************************
 

Status
Not open for further replies.
Toggle Sidebar

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top