                       GPIO Notes for Rivendell

Rivendell supports the following General Purpose Input/Output (GPIO)
devices:

Gameport Joystick Buttons
USB Joystick Buttons
Measurement Computing PCI-PDIS08 Board
Measurement Computing PCI-PDIS16 Board
Measurement Computing PCI-DIO24 Board

Several supported switcher devices feature GPIO capabiities as well,
see the file 'SWITCHERS.txt' for more info.

JOYSTICK DEVICES
Joystick support utilizes the Linux Input Device subsystem.  Inputs
are active-low, and should be wired as follows:

02: Input 1
04: Ground

07: Input 2
05: Ground

10: Input 3
12: Ground

14: Input 4
12: Ground

In addition, you will need to connect 47 kohm resistors between the
following pins:  1-3, 6-8, 9-11 and 13-15.  While not strictly needed
for the GPI portion of the interface to work, the kernel's analog
joystick driver will refuse to initialize the port if these resistors
(or a real joystick) are not present.

The device name of the joystick will be one of the /dev/input/event<n>
devices.

NOTE: There have been reports that some port models do not internally 
connect pin 12 to ground.  The symptom of this situation will be that
Inputs 1 and 2 work, but not Inputs 3 and 4.  If this is the case, 
connecting the ground for Inputs 3 and 4 to pins 04 or 05 should remedy
the problem.


MEASUREMENT COMPUTER GPIO BOARDS
To configure one of the supported MeasurementComputing GPIO boards,
proceed as follows:

1) Install the card(s) in the computer.  In the case of the PCI-DIO24,
   two cards may be necessary, as each seperate card is entirely
   utilized as either inputs or outputs. 


2) Test it out.  Two programs exist for this purpose:  'gpitest' tests
   GPI inputs, and 'gpotest' tests GPO outputs.  These programs come
   with the 'libradio' package.

3) Define a GPIO device in RDAdmin->Stations->Switcher/GPIO.  Use
   a device type of 'Local GPIO'.

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GPIO BOARD-SPECIFIC NOTES

The Measurement Computing PCI-PDIS08 and PCI-PDIS16 boards feature
floating, opto-isolated inputs.  The inputs are not polarity sensitive 
and may be driven by either AC or DC.  The outputs are electro-mechanical
relays with dry contacts.  Connector pinouts are as follows:

PCI-PDIS08 -- DB37 Male Connector
PCI-PDIS16 -- DB37 Male Connector (using C50F-37F Cable)
Pin  Signal
----------------
  1  Input 8/16
 20  Input 8/16

  2  Input 7/15
 21  Input 7/15

  3  Input 6/14
 22  Input 6/14

  4  Input 5/13
 23  Input 5/13

  5  Input 4/12
 24  Input 4/12

  6  Input 3/11
 25  Input 3/11

  7  Input 2/10
 26  Input 2/10

  8  Input 1/9
 27  Input 1/9

  9  Output 8/16 C
 28  Output 8/16 N/O

 10  Output 7/15 C
 29  Output 7/15 N/O

 11  Output 6/14 C
 30  Output 6/14 N/O

 12  Output 5/13 N/C
 13  Output 5/13 N/O
 31  Output 5/13 C

 14  Output 4/12 C
 32  Output 4/12 N/C
 33  Output 4/12 N/O

 15  Output 3/11 N/C
 16  Output 3/11 N/O
 34  Output 3/11 C

 17  Output 2/10 C
 35  Output 2/10 N/C
 36  Output 2/10 N/O

 18  Output 1/9 N/C
 19  Output 1/9 N/O

 37  Output 1/9 C
----------------------
C = Common
N/O = Normally Open
N/C = Normally Closed

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The Measurement Computing PCI-DIO24 board features TTL logic-level 
connections, which can be configured to operate either as inputs or
outputs.  Connector pinouts are as follows:

PCI-DIO24 -- DB37 Male Connector
Pin  Signal
---------------------
 37  Input/Output 1
 36  Input/Output 2
 35  Input/Output 3
 34  Input/Output 4
 33  Input/Output 5
 32  Input/Output 6
 31  Input/Output 7
 30  Input/Output 8
 10  Input/Output 9
  9  Input/Output 10
  8  Input/Output 11
  7  Input/Output 12
  6  Input/Output 13
  5  Input/Output 14
  4  Input/Output 15
  3  Input/Output 16
 29  Input/Output 17
 28  Input/Output 18
 27  Input/Output 19
 26  Input/Output 20
 25  Input/Output 21
 24  Input/Output 22
 23  Input/Output 23
 22  Input/Output 24

 11  Ground
 13  Ground
 15  Ground
 17  Ground
 19  Ground
 21  Ground

 18  +5 VDC
 20  +5 VDC

 16  +12 VDC

 14  -12 VDC

WARNING: The +5 VDC, +12 VDC and -12 VDC pins are connected directly to
the power supply buss of the host PC.  Improper use of these pins can
cause serious damage to your computer!

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