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Kramer Protocol 2000
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11 Kramer Protocol 2000
The
VP-4x8
is compatible with Kramer’s Protocol 2000, version 0.50. This
RS-232/RS-485 communication protocol uses four bytes of information as
defined below. For RS-232, a null-modem connection between the machine
and controller is used. The default data rate is 9600 baud, with no parity, 8
data bits, and 1 stop bit.
Note
: Compatibility with Kramer’s Protocol 2000 does not mean that a
machine uses all of the commands below. Each machine uses a sub-set of
Protocol 2000, according to its needs.
Table 10: Protocol Definitions
MSB
LSB
DESTINATION
INSTRUCTION
0
D
N5
N4
N3
N2
N1
N0
7
6
5
4
3
2
1
0
1st byte
INPUT
1
I6
I5
I4
I3
I2
I1
I0
7
6
5
4
3
2
1
0
2nd byte
OUTPUT
1
O6
O5
O4
O3
O2
O1
O0
7
6
5
4
3
2
1
0
3rd byte
MACHINE NUMBER
1
OVR
X
M4
M3
M2
M1
M0
7
6
5
4
3
2
1
0
4th byte
1
st
BYTE:
Bit 7 – Defined as 0.
D – “ DESTINATION” :
0 - for sending information to the switchers (from the PC);
1 - for sending to the PC (from the switcher).
N5…N0 – “ INSTRUCTION”
The function to be performed by the switcher(s) is defined by the INSTRUCTION (6 bits). Also, if a function is performed
via the machine’s keyboard, then these bits are set with the INSTRUCTION NO. that was performed. The instruction codes
are defined according to the table below (INSTRUCTION NO. is the value to be set for N5…N0).
2
nd
BYTE:
Bit 7 – Defined as 1.
I6…I0 – “ INPUT” .
When switching (i.e. instruction codes 1 and 2), the INPUT (7 bits) is set as the input number which is to be switched.
Similarly, if switching is done via the machine’s front-panel, then these bits are set with the INPUT NUMBER which was
switched. For other operations, these bits are defined according to the table.
3
rd
BYTE:
Bit 7 – Defined as 1.
O6…O0 – “ OUTPUT” .
When switching (ie. instruction codes 1 and 2), the OUTPUT (7 bits) is set as the output number which is to be switched.
Similarly, if switching is done via the machine’s front-panel, then these bits are set with the OUTPUT NUMBER which was
switched. For other operations, these bits are defined according to the table.
4
th
BYTE:
Bit 7 – Defined as 1.
Bit 5 – Don’t care.
OVR – Machine number override.
M4…M0 – MACHINE NUMBER.
Used to address machines in a system via their machine numbers. When several machines are controlled from a single serial
port, they are usually configured together with each machine having an individual machine number. If the OVR bit is set, then
all machine numbers will accept (implement) the command, and the addressed machine will reply.