Advantech ITA-5831 Series, User Manual

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ITA-5831 User Manual 70
chk_smbus_ready(); //wheater SMBUS is ready return
(inportb(SMBU 5)); // Byte value read from SM 5
}
/////////////////////////////////////////////////////////////////////
void smbus_write_byte(BYTE addr, BYTE offset, BYTE value)
// Write SMBUS Register byte value. Write one byte value each time.
addr is slave address (such as 0x40), and offset is register offset
{
int i;
outportb(SMBU 4, addr); // Write slave address to
SM 4 (When writing, slave address bit 0 should be set as 0)
moredelay(); //longerdelay
moredelay(); //longerdelay
chk_smbus_ready(); //wheater SMBUS is ready
outportb(SMBU 3, offset);// write register offset to
SMB_BASE +3.
moredelay(); //longerdelay
moredelay(); //longerdelay
outportb(SMBU 5, value);// Write data value to
SM 5
moredelay(); //longerdelay
moredelay(); //longerdelay
outportb(SMBU 2, 0x48); // Write SMBUS command to
SM 2.. 0x48 means starting byte data transmission.
moredelay(); //longerdelay
moredelay(); //longerdelay
for (i = 0; i <= 0x100; i++)
{
newiodelay();//longerdelay
}
chk_smbus_ready(); //wheater SMBUS is ready
}