GB2319089A

GB2319089A - Apparatus and method for storing and recalling patch bay connections

Info

Publication number: GB2319089A
Application number: GB9622356A
Authority: GB
Inventors: Malcom John Atkin; Thomas Schlum
Original assignee: AIR STUDIOS
Current assignee: AIR STUDIOS
Priority date: 1996-10-28
Filing date: 1996-10-28
Publication date: 1998-05-13
Also published as: GB9622356D0

Abstract

Apparatus and method for patch bay connection storage and recall in which a low current driver associated with each patch jack sends a signal through each patch cable. A detection circuit scans all the other patch jacks to detect this voltage and logs the sending and receiving jack. Latch 33 selects socket 7 for inspection, voltage source 19 when set to L0 provides a voltage to Schmitt trigger 11 if a cable 5 is connected to socket 7 and a further socket e.g. 9. Setting of source 19 to H1 triggers Schmitt trigger 13 at the further socket, thus indicating the cable route. For reconfiguration, the logged routing of each connection is recalled and displayed via a display unit and/or LEDs associated with each jack so that each cable is inserted in the correct jack.

Description

Apparatus and Method for Storing and Recalling Patch Bav Connections The invention relates to apparatus and method for logging connections made in a patch bay and for repatching the bay in an identical configuration at a later date.

More specifically, the invention uses a computer controlled system to analyse the destination of each patch cable. This routing information is then stored in a digital format within the computer so that the patch bay may be reconfigured at a later time.

Professional audio and video production systems used for the creation of music, TV, films and broadcast material utilise thousands of controls and connections. Each control can affect the quality of the finished product. The set-up and adjustment of these controls by the operators and technicians can and does take considerable time.

Each control requires detailed adjustment to achieve the desired sound and/or affect on each program source. The program sources must be routed to and from the various signal processing equipment used in the production. This routing is done through a patch bay. Patch cables are used to make the connections between the signal processing equipment. In addition to the control settings, these cables are an integral part of the final product.

Patch bays, in general, are rows of electrical jacks which connect various signal processing equipment located throughout the production system to a common location and facilitate easy cross connects between equipment. Individual patch cords are connected to the patch bay and route signals from one jack to another. This connection is called a Occasionally, the set-up and adjustment phase of a project may be interrupted by the need to use the production system for another project. In this case, the partially complete set-up must be documented so it may be resumed at a later date.

This documentation of the control and patch bay settings was previously done manually by the operators and technicians using manual techniques. These techniques would include logging settings in a log book and/or taking photographs of the control surfaces. This method of logging the set-up is time consuming and prone to inaccuracy.

A computerised recall system that partially automates the process of logging control settings has been developed by Solid State Logic Ltd and others. These systems utilise an extra potentiometer or switch contact on each control that allows a computer to read and store the control's position. The data read from the controls may later be displayed on a video display unit or like device. The operator may use the displayed information to turn the controls back to their original positions, thus resetting the system to the state it was in when the data was stored.

While the above systems allow the operator a way of resetting the controls of the recording console or other similar equipment, none include the patch bay patching in their data storage. As the patching is a critical element to the overall set-up of the production system, the available equipment is inadequate to perform a complete recall of the set-up.

A standalone patch recall system utilising optical sensors to detect cable placement attempts to overcome the above problem. Such a system is disclosed by W096/02888. This system only stores the sequence in which the patch jacks are plugged into the patch bay and not the absolute routing.

Two ended patch cables must be plugged in an order that the system can recognise, first one end and then the other. Two cables can not be plugged simultaneously.

Therefore, the sequence scheme of W096/02888 can not log patch cable connections in which connection is made between a pair ofjacks in a patch bay as it does not log the routing between a connected pair ofjacks.

The present invention seeks to provide apparatus and method which overcomes the above disadvantages.

In accordance with a first aspect of the present invention, there is provided apparatus for storing and recalling patch bay connections comprising: first detection means for detecting the presence of a connected patch cable in a patch field; transmission means for transmitting a signal through the detected cable; second detection means for detecting the transmitted signal received at the other end of the cable; and storage means for storing the absolute routing the patch cable in response to the first and second detection means.

In a preferred embodiment, first and second detection means comprise means associated with each patch location within the patch field for detecting the presence of a voltage by use of a comparator. A low level voltage source, an isolator associated with each patch location is connected to the voltage source, the output of the isolator being connected to a contact associated with the patch location and input of the associated comparator via a load, the patch cable cooperating with the contact. The comparator may be, for example, a Schmitt trigger. The voltage across the load connected to the jack is compared with a predetermined threshold to indicate the presence of a connected patch cable.

The transmission means may comprise a low current drive associated with each patch location. The low current drive comprises a high level voltage source connected to the isolator so that the current passes through the patch cable via the contact.

The apparatus may further comprise recall means to indicate the absolute routing of the patch cables by use of a visual display unit and/or by an LED associated with each patch location.

Preferably, it is computer controlled, and the output of the first and second detection means is connected to the computer via a bus.

In accordance with a second aspect of the present invention, there is provided a method for storing and recalling patch bay connections comprising the steps of: detecting the presence of a connected patch in a patch field; transmitting a signal through the detected cable; detecting the transmitted signal received at the other end of the cable; and storing the absolute routing of the patch cable in response to the first and second detection means.

Detection may be carried out by scanning each location in the patch field and detecting the presence of a voltage, the voltage being detected by comparing the voltage with a predetermined threshold value.

Transmission may be carried out by generating a low current signal and transmitting the low current signal through the cable.

Preferably, recall of the absolute routing of the patch cables is achieved by displaying on a visual display unit and/or turning on an LED associated with each location on the batch bay.

The present invention, therefore, provides for patch bay connection storage and recall.

The invention uses a low current driver associated with each patch jack to send a small voltage through the shield of each patch cable. Independently, a detection circuit scans all the other patch jacks of the patch bay until it detects this voltage. The sending jack and the receiving jack are then logged by the computer. By sending this small voltage through each cable one at a time and monitoring all other jacks on the patch bay, the routing of any cable may be found and stored for later recall. When the patch bay is to be reconfigured, the previously saved set-up is loaded into the computer. The operator is informed of the correct patching by LEDs associated with each patch jack. The computer lights two LEDs and waits for the operator to plug a patch cable between the two jacks associated with the LEDs. Once the cable is in place, the computer will automatically advance to the next patch and lights the LEDs associated with the next patch. In this manner, each patch cable is replaced, configuring the patch bay as it was the previous set-up.

The present invention will now be described in more detail by means of the following description of a preferred embodiment and with reference to the following figures in which: Figure 1 shows the circuit arrangement of the preferred embodiment of the present invention; and Figure 2 shows a partial view of the front panel of the patch bay of the preferred embodiment of the present invention.

Figure 1 shows only two patch jacks and their associated circuitry to detect and display patch cable connections. It is realised that in an actual system there will be a large number ofjacks, each having associated circuitry as shown by Figure 2. This figure shows a partial view of the front panel of the patch bay of the present invention. The panel comprises two rows of sockets 7, 9 and associated LEDs 25, 27.

The bay may comprise a plurality of units shown in Figure 2, stacked to provide a large number of locations within the field.

A pair of plugs 1, 3 are connected at either end of a patch cable 5. The patch cable 5 comprises a balance line. Each plug 1, 3 is placed in its associated jack apertures 7, 9 as shown in Figure 2 with associated electrical contacts 8, 10 to provide a desired patch connection.

A contact 12, 14 contacts the plug 1, 3 and is connected to the input of a Schmitt trigger 11, 13 via a series resistor 15, 17.

An adjustable reference voltage source 19 is connected to an opto-isolator 21 and 23 associated with each jack 7 and 9 respectively and drives an associated LED 25, 27 as shown in Figure 2. The output of the opto-isolator 21, 23 is connected to a load comprising series connected resistors 29 and 15, 31 and 17. The input of the optoisolator 21, 23 is connected to the output of respective D-type latches 33, 35.

The circuit is controlled by a computer 35. The reference voltage source 19, the input of the D-type latches 33, 35 and the output of the Schmitt triggers 11, 13 are connected to the computer via a parallel interface bus 37 connected to the printer port of the computer 35. The computer 35 is connected to a visual display unit 39 and keyboard 41. It may also be optionally connected to a printer and/or disc drive etc.

In operation, the computer 35 sets the level of the reference voltage generated by the voltage source 19 to a low value. It then sets the data latch 33 to the on state. This turns on the opto-isolator 21. A voltage is then dropped across the voltage divider 29, 30. The computer then reads the state of Schmitt trigger 11.

If a connected cable e.g. a cable connected between patch jack apertures or connected to ground, is plugged into patch jack aperture 7, the voltage between the resistors 29, 30 connected to the input of the Schmitt trigger 11 is below the threshold. Therefore, the output of the Schmitt trigger 11 is low. If the patch cable is not connected or no cable is present, the voltage is above the threshold of the Schmitt trigger 11 and the output would be high. The output of the Schmitt trigger is registered by the computer via the parallel interface bus 37 and the status of the particular aperture is stored.

If there is a connected patch cable 5 plugged into the patch jack aperture 7, the computer then sets the reference voltage to a high value. The current from the jack aperture 7 passes through the shield of patch cable 5 and appears at patch jack aperture 9 and resistor 17. The output state of the Schmitt trigger 13 is affected by the current feeding through the patch cable. The computer scans and detects the state on the output of the Schmitt trigger 13 via the same parallel interface bus 37 as before.

This is then repeated by scanning each aperture within the patch field, applying a low reference voltage to detect a connected patch cable and detecting the routing of the cable by applying a high reference voltage as above.

This connection or no connection data for each jack aperture is stored in the computer for later recall. For recall and re-plugging, the computer displays the stored data on both the computer's display unit 39 and by turning on the LEDs 25, 27. Through the interface bus 37, the computer sets the data latches 33 and 35. This in turn lights the LEDs 25, 27 associated with each patch jack aperture. In this way the user is shown the correct jacks to plug the patch cables if. If an incorrect connection is made, the LED flashes until the jack is plugged in the correct location. Once the connection is made, the computer moves to the next connection to be made by lighting the next pair of LEDs. In this way, the patch cables are plugged into the patch field in the correct order, one at a time.

Therefore, the absolute routing of a patch cable can be logged and recalled as required. Furthermore, if a connection is broken, it can easily be recalled by reference to the stored data.

In the light of the disclosure, modifications of the described embodiment, all within the scope of the appended claims, will now become apparent to persons skilled in the art.

Claims

CLAIMS:

1. Apparatus for storing and recalling patch bay connections comprising: first detection means for detecting the presence of a connected patch cable in a patch field; transmission means for transmitting a signal through the detected cable; second detection means for detecting the transmitted signal received at the other end of the cable; and storage means for storing the absolute routing of the patch cable in response to the first and second detection means.

2. Apparatus according to claim 1, wherein first and second detection means comprise means associated with each patch location for detecting the presence of a voltage.

3. Apparatus according to any one of the preceding claims, wherein said transmission means comprises a low current drive associated with each patch location.

4. Apparatus according to claim 3, wherein said first and second detection means comprises a comparator connected to each associated patch location.

5. Apparatus according to claim 4, wherein said first detection means further comprises a low level voltage source, an isolator associated with each patch location connected to said voltage source, the output of the isolator being connected to a contact associated with said patch location and input of the associated comparator via a respective load, the patch cable cooperating with the contact.

6. Apparatus according to claim 5, wherein said low current drive comprises a high level voltage source connected to said isolator so that the current passes through the patch cable via the contact.

7. Apparatus according to any one of claims 4 to 6, wherein the comparator is a Schmitt trigger.

8. Apparatus according to any one of the preceding claims, wherein the apparatus further comprises recall means to indicate the absolute routing of the patch cables.

9. Apparatus according to claim 8, wherein the patch locations having connected patch cables are displayed on a visual display unit.

10. Apparatus according to claim 8 or claim 9, wherein the locations of the first and second patch connectors are displayed by an LED associated with each patch location.

11. Apparatus according to any one of the preceding claims, wherein the apparatus is computer controlled.

12. Apparatus according to claim 11, wherein the output of the first and second detection means is connected to the computer via bus means.

13. A method for storing and recalling patch bay connections comprising the steps of: detecting the presence of a connected patch cable in a patch field; transmitting a signal through the detected cable; detecting the transmitted signal received at the other end of the cable; and storing the absolute routing of the patch cable in response to the first and second detection means.

14. A method according to claim 13, wherein the steps of detection comprise scanning each location in the patch field and detecting the presence of a voltage.

15. A method according to claim 14, wherein the voltage is detected by comparing the voltage at each patch location with a predetermined threshold value.

16. A method according to claim 14 or claim 15, wherein the transmission step comprises generating a low current signal and transmitting the low current signal through the cable.

17. A method according to any one of claims 13 to 16, wherein the method further comprises recalling the absolute routing of each cable.

18. A method according to claim 17, wherein the recall step comprises displaying the location of each connected cable.

19. A method according to claim 17 or claim 18, wherein the recall step further comprises displaying the location by turning on an LED associated with each location.

20. Apparatus for storing and recalling patch bay connections substantially as hereinbefore described with reference to the accompanying figure.

21. A method for storing and recalling patch bay connections, the method substantially as hereinbefore described with reference to the accompanying figure.