MCP23s08 help ?

[dikris]

Hi all,
 
I have CCS project with PIC18f452 and 8 mcp23s08.I want to make  4 of them inputs with pull-up and another 4 - Outputs.I use hardware addressing pin(A0,A1) . Inputs and otputs have separately CS.
Can you advice me how to init those chips.When I send command to outputs all 4 chips recive same information.Any driver idea.
 
I wrote this driver:
 
void init_SPI()
{
output_low(SPI_CLK);
 delay_us(50);
output_low(SPI_DI);
output_high(OUTPUTS_CS);
output_high(INPUTS_CS);
   delay_us(50);
}
void mcp32s08_SendByte(BYTE data)
{
   BYTE i;
 delay_us(2);
  for(i=0; i<8; ++i)  //SEND DATA
 {
   if(bit_test(data, 7))
   output_high(SPI_DI);
  else      
   output_low(SPI_DI);
     // data=data>>1;
      delay_us(60);
      output_high(SPI_CLK);
      delay_us(40);
    output_low(SPI_CLK);
    data <<= 1;
   }
}

void mcp32s08_write(BYTE address,BYTE reg,BYTE value,BYTE io)
{
  output_low(SPI_CLK);
  output_low(SPI_DI);
if(io==0)                 //outputs
output_low(OUTPUTS_CS);
else                        //inputs
output_low(INPUTS_CS);

 mcp32s08_SendByte(address);  //SEND OP CODE (ADDRESS)
 mcp32s08_SendByte(reg); //SEND REGISTER
 mcp32s08_SendByte(value);  //SEND VALUE
 init_SPI();
}

void mcp32s08_SetPulUp(BYTE address)
{
 address=address<<1;
 address=0x40+address;
mcp32s08_write(address,MCP23s08_GPPU,0xFF,1);
}
 
void mcp32s08_SetIOCON(BYTE address,BYTE dir)
{
 address=address<<1;
 address=0x40+address;
mcp32s08_write(address,MCP23s08_IOCON,0x04,dir);
}
 
void mcp32s08_Out(BYTE address,BYTE value)
{
 address=address<<1;
 address=0x40+address;
mcp32s08_write(address,MCP23s08_GPIO,value,0);
}

void mcp32s08_init(BYTE address,BYTE dir)
{
BYTE value;
 address=address<<1;
 address=0x40+address;
if(dir==1)
 value=0xFF;
else
 value=0x00;
mcp32s08_write(address,MCP23s08_IODIR,value,dir);
}
 
 
And the code of init is:
 
 for(i=0; i<4; ++i)  //INPUTS
 {
mcp32s08_SetIOCON(i,1);
mcp32s08_SetPulUp(i);  //Pull Up - Internal
mcp32s08_init(i,1);  
 }
  for(i=0; i<4; ++i)  //OUTS
 {
  mcp32s08_SetIOCON(i,0);
  mcp32s08_init(i,0);
  mcp32s08_Out(i,0x00);   //All Outs '0'
 }
 
  mcp32s08_Out(0,0x01); //Here is the problem

After this bit 0 of all outs is 1, not 1 on first chip only.
 
Sorry of my English.

[bbarney]

maybe this will help

[dikris]

The book describe I2C. MCP23s08 -> SPI, MCP23008 -> I2C.

[robban]

I can't find any significant error in Yr. code, but if I were You I should fiddle a little bit with the delay routines(timining can be critical when talking to external modules). I assume You have connected the hardware and pullup resistors OK.

Good Luck!:)

[robban]

You wrote:
mcp32s08_write(address,MCP23s08_IOCON,0x04,dir);
 
The rest of the code constitute "dir" as "BYTE dir". By the way, when You send us code, don't be sparse with comments and line numbers.

[dikris]

Thanks a lot.
 
void mcp32s08_SetIOCON(BYTE address,BYTE dir) //dir mean INPUTS-1 and OUTPUT - 0
{
address=address<<1;
address=0x40+address;
//mcp32s08_write(address,MCP23s08_IOCON,0x04,dir); //WRONG VALUE - 0x04
 
 // HAEN(hardware address enable) is bit 3  ->  0x08 from IOCON Register
                                                                   
mcp32s08_write(address,MCP23s08_IOCON,0x08,dir); //CORRECT VALUE
}

[dikris]

All registers from one of the MCP23s08(inputs) via RS232

IODIR=FF
IPOL=00
GPINTEN=00
DEFVAL=00
INTCON=00
IOCON=08
GPPU=00
INTF=00
INTCAP=00
GPIO=FF
OLAT=00

[bbarney]

sorry about that i just woke up when i read your post

[robban]

Hi Dikris!
Glad You made it...