panel buttons to cycle the address from Master, to Slave 1, to Slave 2 and then back to Master. As the address cycles, you will see the port number on the front panel LED's changing between the following combinations:

1 2 3 4 or 5 6 7 8 or 9 10 11 12

When you have the proper address selected, press and hold down simultaneously the buttons of port A and port D on the unit. When the LED's stop blinking, this will indicate that the address has been set. (about 3 seconds)

Serial Control:

You may only change the address of the MC4-H2unit that you are connected to via a serial cable. Send the following command to the MC4-H2to change the address of the box, which you are connected to via the serial cable.

Ax - where "x” is the address you want this unit to have.

The address commands are "M" for Master, "1" for Slave 1, and "2" for Slave 2 Examples:

AM - set this unit's address to Master (Ports 1-4)

A1 - set this unit's address to Slave 1 (Ports 5-8)

When an address is changed, that unit announces it’s new address to any other MC4-H2’sthat it is connected to via the chain cable. If any unit already has this address, it will loose it’s address to the unit that just changed addresses. Here is an example. Let’s say you have two MC4-H2’s. Call them Unit A and Unit B. Unit A is set as the Master and Unit B is set as the Slave 1. If you were to change the address of Unit B to the master, Unit A will have to give up it’s address since Unit B has now taken the Master address. Unit A will now not have an address and the LED’s will be blinking “00”. Give Unit A an address by following the front panel method or the serial method.

Note: If a unit has no address, the LED’s are flashing “00”, you will still need to hold down the buttons on port A and port D for 3 seconds and the press any front panel button to select a new address and then continue with the Front Panel address changing method.

Stacking (Daisy-Chaining) of Multiple MC4-H2 Units

In order to connect two or more units to expand the number of PC’s that you control, you need to order a Daisy-Chain Cable Set. Connect the OUT of the Slave #1 to the IN of the Master. If you have a 2nd slave connect the OUT of it to the IN of Slave #1. The Power Supply connected to the master unit will power up the Slave Units through the expansion port. However there is no damage if you connect supplies to the slaves and in fact it is recommended when you have 3 units.

FIGURE 3 Stacking of MC4-H2 Units

Hot Swapping Mice and Keyboards

Hot swapping is not recommended but may be successfully performed. You may unplug the mouse and/or the keyboard while the MC4-H2is powered up and PC’s are connected and powered on. You may then plug in the same keyboard/mouse or a different keyboard/mouse and the MC4-H2will recognize the new keyboard/mouse.

Hot Swapping PC’s

You may hot swap a PC while the MC4-H2is powered up only after that PC has been turned off. After the PC has been turned off, unplug the keyboard, mouse, and video connectors of the CA10087 (4-in-1) cable then plug them into the PC you wish to insert into the MC4-H2setup. Then power on the new PC.

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