Crown Audio IQ-USM 810 service manual What is preset P00?

IQ-USM 810 Service Manual 130447-1 Rev. A

will cause the IQ-USM 810 to automatically reboot. If the top cover is off the unit, switch S1 on the System Controller board (the long board with the rear panel DB9F and DB37M connectors) will reboot the unit. The LED located next to the switch is lit when the unit is not in reset.

Q. I notice there is a switch on the SHARC board. What is it for?

A. The switch on the SHARC board resets the SHARC processors independently of the System Controller. The problem with using this switch to reset the SHARC pro- cessors is they need the System Controller to reboot them. In practice, the SHARC board reset switch is not used. The LED by the switch lights when the SHARC's are not in reset. Reset is controlled by the System Con- troller. If a reboot of the SHARC's is required, use the System Controller reset switch to reset the entire IQ- USM 810 and reboot the SHARC's.

Q. I plug in the IQ-USM 810 and nothing happens. What's the matter?

A. First, ensure that AC power is indeed being applied to the unit. Next, take the cover off the unit and see if any of the LED's on the System Controller or SHARC boards are lit. If so, check the cable between the Sys- tem Controller board and Front Display board. If no LED's are lit, check the cable between the power sup- ply (located under the System Controller board) and the System Controller. If that seems OK, check the power supply by removing the System Controller. A fuse is lo- cated on the power supply board. Replace ONLY with the same type fuse.

Q. What is preset “P00?”

A. Preset P00 is a factory default preset that allows the IQ-USM 810 to be placed into a known, safe state. In P00, all faders are at minimum and all filters, gates,

delays, etc. are off. It is a good place to start when start- ing to configure a unit or if you need to get back to a known starting point.

Q. What is the purpose of the “Infinity Pattern” on the front panel?

A. The Infinity pattern is also referred to as a “test” pat- tern. It’s serves no real purpose other than to provide an attractive display when front panel level or gate sta- tus indication is not desired.

Q. How should I set the baud rate on the IQ-USM 810?

A. The baud rate for the RS232 interface is adjustable and is accessed by the front panel (see the Reference Manual for information on settng the baud rate). In prac- tice, you should try to run at as a fast a rate as you can without problems. Some computers have difficulties keeping up at 115 k baud. If you notice the IQ-USM 810 dropping off-line occasionally, try a slower baud rate. The IQ for Windows software automatically adjusts to the selected baud rate of the IQ-USM 810 during initialization, so no setup of the software is required.

Q. Why don't I have a control to set the baud rate of the IQ loop?

A.The IQ loop's baud rate is fixed at 38.4 k baud and is not adjustable.

Q.What voltage should I use to wire analog control pots to the IQ-USM 810's Control Port?

A.The IQ-USM 810 needs a 0 to +10V voltage to utilize the full range of the Control Port's analog inputs. +10VDC is provided on the Control Port connector for this pur- pose. If you want the remote pot to control only a por- tion of the fader range, use the IQ for Windows software to tailor the range desired. In general, the Control Port pots should be wired between GND and +10VDC.

4-10 Maintenance

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