Modes of Operation

The GX6264 has two modes of operation that can be used in combination. These modes of operation and their combined use are described in the following paragraphs.

Direct Mode

The GX6264 has 8 scan groups. Each group consists of 8 differential inputs routed to its dedicated bus.

The scanning function ensures that only one differential channel can be connected to the scan group bus at the time.

The following figure shows the layout of scan group A. Scan groups B-H are identical. In the direct mode each of the eight scan groups act as an independent Scanner/Multiplexer unit.

Scan Group A

Universal Bus Mode

 In this mode, each section acts as a 32x2 differential matrix. The figure below shows the layout of the first matrix complete with the individual group channels. The layout allows groups to be operated individually or in combination to form larger groups or to implement a channel-to-channel connection from one group to another.

Universal Bus Mode - Section - 1

Single Ended Switching

The buses X0, X1, Y0 and Y1 (Universal Buses) contain a switching circuit that can be configured in different ways to enable a Single Ended mode. This mode is individually selectable for each Universal Bus allowing combined Single Ended and Differential mode operation with having some Universal Buses switched to single ended and some to differential.

The figure shows the Single Ended Mode with scan group A through X0 bus.

Single Ended Mode

In the Single Ended mode, either the Hi or the Lo side of a scan group bus is selected and connected to the Hi side of the Universal Bus. The Lo side of the Universal Bus is open (not connected).

An alternative configuration is available by installing jumpers JP8, JP9, JP12 or JP13. This connects the Lo side of the Universal Bus to analog ground (AGND). JP8 connects the Y0 bus, JP9 the X0 bus, JP12 the Y1 bus, and JP13 connects the X1 bus.

Combination of Switching Modes

The direct bus mode and the universal bus mode in differential or single ended switching can be use simultaneously and combined on a group by group basis.

Grounds

There are three ground signals on the GX6264; Logic ground (GND), Analog ground (AGND) and Chassis ground (Chassis). All of the shielding on the GX6264 board is connected to the Chassis ground signal. Logic ground is the power supply return and Analog ground (AGND) is only connected to the user connectors, J6 and J7. JP1 can be installed to connect the Chassis ground to Logic ground. JP2 can be installed to connect the Analog ground to Logic ground and JP5 can be installed to connect the Chassis ground to Analog ground.