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D-70 / Apr 2000
CPU & DSP
address to communicate with the console. The address is set with the jumpers
in binary format (for example with all jumpers removed the address is “0”,
with the first jumper inserted, the address is “1”, with just the second jumper
inserted the address is “2”, with the first and second jumpers inserted the
address is “3” and so on). Consult the section “Internal Programming
Options”, page 6-6, for more details. The D-70 console is normally configured
with an address of “1”. Do not change the console address unless you are using
the console in an RS-485 bus system.
2. The second function is serial interface configuration. Jumpers J1-J4 on
the PR-70 PCB control the serial interface protocol and R-485 termination for
the serial port. This port can be configured as RS-232 or RS-485, and
terminated or unterminated via these jumpers. Again, the default settings are
for normal operations and should not be changed unless you are using the
console in an RS-485 bus system. Consult the sections “D-70 Serial Inter-
face”, page 6-4, and “Internal Programming Options”, page 6-6 to page 6-7,
for specific configurations. Jumper J38 is also used with the serial interface;
by installing it, the normal checksum in the serial protocol is disabled. This can
be useful with some external control devices which are not equipped to
generate a checksum in their messages.
3. The third function is nominal audio make-up gain. Jumpers J37, J39 and
J43 on the PR-70 PCB are used to establish the master gain setting for the
D-70 console. This allows users to configure the nominal fader setting and
signal headroom to suit their specific needs or preferences. The digital audio
signals entering the D-70 console are usually normalized in the recording or
transmitting process for peak signals such that the absolute maximum peak
signal is very close to, but does not exceed, the maximum or highest digital
word in the AES bit stream. This implies that any decrease in signal caused
by placing the console fader at a “normal” setting somewhat less than full up
needs to be made up at the output of the console or the signal will be lower than
it was at the source. Radio consoles are normally operated with their faders at
less than full up to allow for some control over level and mixing ( if a signal
is too low or quiet, the fader can be moved up until the signal matches the
normal levels as shown in the console meters.). By using the jumpers, the user
can configure what the normal fader setting (and hence the output make-up
gain) should be. Consult the “Global Gain” table in the “Internal Program-
ming Options” section, page 6-6, for the gain values. The D-70 console is
normally shipped with a make-up gain setting of +12dB for a nominal fader
setting of -12dB from the top. Note that setting the make-up gain too high for
the signals and fader settings used can result in a clipped or distorted signal,
just as it could with an analog console.
4. The fourth function is serial interface control. The front panel of the
CRD-70 module has a pushbutton switch. Activating this switch will enable
the remote serial interface to the console, and de-activating the switch will
disable the remote serial interface. When the interface is activated, any device
D-70 / Aug 2000
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