Technical Information
DAFV
2
Protocols and DIP Switches
This document covers the serial RS-422 protocol used by the JLCooper Electronics
DAFV
2
ESAM/GVG-to-Digital Mixer converter. It also covers DIP switch settings.
Electrical
As implemented on the DAFV
2
, the RS-422 protocol is at 38.4 kBaud, with 8 data
bits and one parity bit. Parity Odd/Even is automatically set.
The RS-422 comes into the DAFV
2
via a 9-pin female Sub D connector on the rear.
The pin-out conforms to SMPTE #113 standards, and is as follows:
Pin 1 - Ground
Pin 6 - Ground
Pin 2 - Output (-)
Pin 7 - Output (+)
Pin 3 - Input (+)
Pin 8 - Input (-)
Pin 4 - Ground
Pin 9 - Ground
Pin 5 - no connection
DAFV
2
can be used in an eavesdrop mode, that is, connected to a video switcher
output via a “y” cord. If this is done, a cable with pins 2 and 7 disconnected will be
needed to prevent DAFV
2
’s tallybacks from interfering with the video switcher’s
tallybacks.
ESAM Protocol
Note: All numberrs in hex.
When the DAFV
2
is first turned on, it is in an idle state.
In order to select the unit, the following bytes must be sent:
<break> 88 A6 03
. This string should only be sent once to select the DAFV
2
.
After this, normal commands may be sent.
The following are the commands recognized by the DAFV
2
:
a) Transition Command -
03 01 A9 C0
Upon receipt of this string, the DAFV
2
will send back an 80 as acknowledgment, and
will start a transition at the currently active transition rate.
b) Transition Rate Command -
04 01 A7 00 rr
Upon receipt of this string, the DAFV
2
will send back an 80 as acknowledgment, and
will store rr as the transition rate in frames.
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