Important, Calculating the
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Command Mode continued:

stands for CHECKSUM: the value is

calculated by performing an XOR of the full com-

mand string. For example: //F00M12I03 will XOR

to the hexadecimal value 0x42, therefore the value

of is 0x42.

CALCULATING THE

IMPORTANT

5) To query crosspoints from PC:

//FxxU

• If all outputs are connected to input 1 then a 4x4 Matrix will respond

with

<0x80><0x80><0x80><0x80>

• The router will send back one byte for each output and the string

ends with a . The first byte sent is Output #1. In the example

above, since there are 5 bytes total, we know that there are 4

outputs.

• To calculate the input number, the router sends the input number

with the 7th bit set.

0x80 = “1000 0000” input 0

0x81 = “1000 0001” input 1

…

0x8F “1000 1111” input 15

Notes:

When successful, commands #1-4 will acknowledge by sending the

checksum with nibbles swapped &

e.g. checksum of 0x24 acknowledges with <0x42>

Using RS-232 Control (continued)

This manual is related to the following products:

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