PCI-DDA0X-16 Version 0.3
                      ----------------------

 Linux loadable module for the Computer Boards PCI-DDA0X-16
 ------------------------------------------------------------------------

NOTE:  kernel 2.6 driver is called:  dda0X-16_2_6.c

Introduction:
-------------

This driver was written by Warren J. Jasper at North Carolina State
University.  It is a driver for the ComputerBoards PCI-DDA0X-16
adapter.  

Please send comments and bug fixes to wjasper@tx.ncsu.edu.  The source for the
driver is located at ftp://lx10.tx.ncsu.edu/pub/Linux/drivers.


Distribution contents:
----------------------

README                 - this file
Makefile               - Makefile to compile and install the driver
dda0X-16.c             - PCI-DDA0X-16 Driver source.
dda0X-16_2_6.c         - PCI-DDA0X-16 Driver source 2.6 Kernel
dda0X-16.h             - Driver definitions and constants.
test-dda0X-16.c        - Test program.
RegMapPCI-DDA0x-16.pdf - Register Map

Building and installing the driver:
-----------------------------------

1. Untar the tar file:

   tar zxvf PCI-DDA0X-16.0.1.tgz

2. This should create the following files:
    README  
    Makefile
    dda0X-16.c
    ddda0X-16_2_6.c
    dda0X-16.h
    pci-dda0X-16.h	
    test-dda0X-16.c
    RegMapPCI-DDA0x-16.pdf

3. The default configuration is for the kernel to dynamically set the
   major number.  If you wish to override this option and force a particular
   major number, set the following in dda0X-16.h

   #define DEFAULT_MAJOR_DEV  0    /* Default Major Device Number */
 
4. To compile, type:

   make

5. To install the driver type:

    make install

  check that the destination directory is correct.

6. Copy the file 60-mcc.rules to /etc/udev/rules.d.  This files can be found
   at ftp://lx10.tx.ncsu.edu/pub/Linux/drivers

   or inlcude the following rules:

#Enable non-root access to pci devices
SUBSYSTEM=="dda0x-16", KERNEL=="da[0-9]_[0-7]", NAME="dda0x-16/%k", MODE="666"
SUBSYSTEM=="dda0x-16", KERNEL=="dio[0-9]_*",    NAME="dda0x-16/%k", MODE="666"

To test your updated rules you can run:

   /sbin/udevcontrol reload_rules


Having the driver install at boot:
----------------------------------
There are 2 ways to do this:


1) To install the driver so that it comes up every time on boot-up, you
  will need to include the following lines in one of your boot rc files.
  The one we used is called /etc/rc.d/rc.local. Your setup may vary.

#! /bin/sh
#
# rc.local	This does local customization.
#
# Author:	Warren Jasper <wjasper@tx.ncsu.edu>
#
echo -n "Local customization:"

if [ -x /sbin/insmod -a -r /lib/modules/`uname -r`/kernel/drivers/char/dda0X-16.ko ]; then
    echo -n " PCI-DDA0X-16"
    /sbin/insmod -f /lib/modules/`uname -r`/kernel/drivers/char/dda0X-16.ko
fi


2)  add the following line to your /etc/modules.conf or /etc/modprobe.conf

        alias char-major-244  dda0X-16.ko


Multiple Boards
--------------
The driver supports the pci-dda02-16, pci-dd04-16, and the pci-dda08-16.  These differ only
in the number of DAC channels (2, 4, or 8 respectively).  The driver will auto detect which
board you have, and only let you open the correct number of DAC channels.  If you have
multiple boards,  edit the Makefile and dda0X-16.h for the macro NUM_BOARDS and change it
from 1 (default) to the number that you have.  Than type "make devices", "make", "make install".


How the driver works:
---------------------

The driver is fairly straight forward, but since the current version of
Linux is not 1003.4 compliant (it is not a real-time operating system),
certain design decisions were made in writing this driver. 

The device name for the driver is:

/dev/dda0x-16/da[Board Number]_[Channel Number]
/dev/dda0x-16/dio[Board Number]_[Port Number]

where:
     Board Number is the number of the board, usually 0 if you only have 1 board
     Channel Number is the DAC channel number [0-7]
     Port Number is the 8255 Port name {0A, 0B, 0C, 1A, 1B, 1C}

For example:

fd_1 = open("/dev/dda0x-16/da0_0", O_RDWR );
fd_2 = open("/dev/dda0x-16/dio0_0A", O_RDWR );


****************************************************************************

The following ioctl() functions have been implemented:

1. ioctl(fd, DIO_SET_DIRECTION, PORT_INPUT);
   Set the direction of the port to either input or output.  Port C can be split
   into two levels (4 bits each), while ports A and B are either all input or
   all output.

2. ioctl(fd, DAC_SET_GAINS, gain);
   Sets the gain for the given channel.  Allowed values for gain are found in
   pci-dda0X-16.h and they are:
  
          BP_2_5V    +/- 2.5V  Full Scale
          BP_5_0V    +/- 5.0V  Full Scale
          BP_10_0V   +/- 10.0V Full Scale
          UP_2_5V    0 - 2.5V  Full Scale
          UP_5_0V    0 - 5.0V  Full Scale
          UP_10_0V   0 - 10.0V Full Scale

3. ioctl(fd, DAC_GET_GAINS, &gain);
   get the current gain for the channel.

4. ioctl(fd, DAC_ENABLE, 0);
   Enable the DAC for output.

5. ioctl(fd, DAC_DISABLE, 0);
   DISABLE the DAC for output.  Output is zero.

6. ioctl(fd, DAC_SIMULT_UPDATE, 0);
     Updates all the channels simultaneously.

7. ioctl(fd, DAC_SET_SIMULT, value);
      value = 0 false/disable  1 = true/enable
      if enabled, that channel will update simultaneously.  See documentation.

8. ioctl(fd, DAC_GET_SIMULT, &value);
        value = 0 false/disable  1 = true/enable