Ashly VCM-88C, Operating Manual

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Operator Manual – VCM-88C Controller Page - 9
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Data Connections & Configurations
Remote Data Control
To connect the RD-8C, RW-8C or other compatible remote controller, the VCM-88C uses
a three-pin euroblock connector. Data can be sent through one channel of a standard audio
snake without affecting adjacent audio channels. Do not use an isolation transformer in the
data line. Connect the three pins to the same pins on the RD-8C/RW-8C remotes as
labeled. Be sure to set the VCM-88C protocol to the RD-8C/RW-8C on the rear panel DIP
switches.
The Standard data protocol is compatible with current AMX and Crestron controllers. Both
AMX and Crestron provide hardware which interfaces with the VCM-88C. To learn more
about their control systems, visit their websites at
www.amx.com and www.crestron.com .
The details of the Standard VCM-88C protocol are as follows: The three connector pins
are labeled:
G (ground), V+ (+20VDC for RD-8c/RW-8C controllers), and D (Data). Do
not use the V+ pin with 3rd party hardware such as AMX or Crestron.
A valid message consists of two bytes with no break between byte1 and byte 2.
1 Byte = start bit + 8 data bits + stop bit (10 bits total, no parity)
Baud rate: 9600 bps
Start bit: logical 0 (current on) Stop bit: logical 1 (current off)
Byte 1: Channel ID Character:
hex 80 - hex FF = Channels 1 - 128 Byte 2: Channel Level Character:
hex 7F = full on = +20.25dB
hex 64 = unity gain = 0dB
hex 00 = off = -75dB
(step size = 0.75dB)
AMX and Legacy
Older AMX products using the VCX-80 driver, require the Legacy data protocol setting on
the VCM-88C rear panel DIP Switches.
DC Control Voltage Connection
Direct DC voltage control of internal VCA circuits is available on the VCM-88C via a 12
pin euroblock connector. DC control allows for custom “low-tech” hardware interfaces.
Two wires are used to supply positive and negative DC voltage to ordinary 10K ohm
linear-taper potentiometers, and a wire is used to return the wiper of each control to its
respective channel (see pinout below). Telephone wire with eleven conductors or more is a
good choice for this application, and since only DC voltage is used, control line distance is
not a major concern.
Pin 1 Channel 1 DC control input Pin 7 Channel 7 DC control input
Pin 2 Channel 2 DC control input Pin 8 Channel 8 DC control input
Pin 3 Channel 3 DC control input Pin 9 Master DC control input
Pin 4 Channel 4 DC control input Pin 10 +15VDC - Connect to pot CCW
Pin 5 Channel 5 DC control input Pin 11 (Ground for data input)
Pin 6 Channel 6 DC control input Pin 12 -4VDC - Connect to pot CW
Safety Instructions – 3
Introduction - 4
VCM-88C Controller – 5
Connectors & Cables - 5
Physical Description - 6
Installation – 7
Applications - 8
Data Connections – 9
Remote Data Control
AMX & Legacy
DC Control
RS-232
Troubleshooting – 11
Dimensions - 11
Specifications - 12
Warranty - 13