Digital I/O Wildcard User Guide

Controlling the I/O Lines

Once you have set the direction of the I/O lines, you can read and set the I/O lines like the other digital I/O ports on the Mosaic controller.

C Code to control the Digital I/O Wildcard

#define OUTPUT_HIGH	1
#define OUTPUT_LOW	0

#define NIBBLE_0_ADDR	0xC000 // Lines 0-3.
#define NIBBLE_1_ADDR	0xC001 // Lines 4-7.
#define NIBBLE_2_ADDR	0xC002 // Lines 8-11.
#define NIBBLE_3_ADDR	0xC003 // Lines 12-15.
#define NIBBLE_4_ADDR	0xC004 // Lines 16-19. Inputs only

#define LINE_0	1
#define LINE_1	2
#define LINE_2	4
#define LINE_3	8
#define LINE_4	1
#define LINE_5	2
#define LINE_6	4
#define LINE_7	8
#define LINE_8	1
#define LINE_9	2
#define LINE_10	4
#define LINE_11	8
#define LINE_12	1
#define LINE_13	2
#define LINE_14	4
#define LINE_15	8

void Control_DIO ( uchar mod_num, uint nibble_addr, uchar line, uchar state )
// Sets I/O line of specified nibble to the appropriate state (high or low).
// Valid module (ie Wildcard) numbers are 0-7.
// Valid nibble addresses are NIBBLE_0_ADDR to NIBBLE_3_ADDR.
// Valid lines are LINE_0 to LINE_15
// Valid states are OUTPUT_HIGH or OUTPUT_LOW
{
EXTENDED_ADDR module_addr;

module_addr.sixteen_bit.page16 = mod_num;
module_addr.sixteen_bit.addr16 = nibble_addr;

if(state) // set line high
{
SetBits( line, module_addr.addr32 );
}
else // set line low
{
ClearBits ( line, module_addr.addr32 );
}
}

uchar Read_Nibble ( uchar module_number, uint nibble_addr )
// Reads the current state of the Digital I/O nibble.
// Valid module numbers are 0-7.
// Valid nibble addresses are NIBBLE_0_ADDR to NIBBLE_4_ADDR.
// Returns an unsigned character whose least significant nibble represents
// the four I/O lines. For example, if nibble 1 is read and a 1 is returned
// (0001 in binary), then line 4 is high and lines 5-7 are low. If 12 is
// returned (1100 in binary) after reading nibble 3, then lines 12 and 13 are
// low and lines 14 and 15 are high. The four most significant bits of the
// returned byte do not matter.
{
EXTENDED_ADDR module_addr;
uchar nibble_status;

module_addr.sixteen_bit.page16 = module_number;
module_addr.sixteen_bit.addr16 = nibble_addr;

nibble_status = FetchChar( module_addr.addr32 );

return( nibble_status );
}

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Digital I/O Wildcard User Guide

Controlling the I/O Lines

C Code to control the Digital I/O Wildcard