I/O Driver Functions
The following code sample is taken from a working driver file implemented to support the ONYX-MM-DIO I/O card from Diamond Systems Corp.
sysOutByte(onyx_base_addr+ DIO_2A,0x00); /* Reset of output registers before setting of 2A portaddr = onyx_base_addr+DIO_1CR; /* control register 1CR address */addr = onyx_base_addr + DIO_2CR; /* control register 2CR address */sysOutByte(addr,0x9B); /* Port 2A , 2B and 2C set to INPUT/MODE 0 */