Table 4: protocol definitions, Table 5: instruction codes for protocol 2000, Kramer protocol – Kramer Electronics PL-8 User Manual
Page 16: 13 table 4: protocol definitions

Kramer Protocol
13
Table 4: Protocol Definitions
MSB
LSB
DESTI-
NATION
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 that is to be performed by the switcher(s) is defined by the INSTRUCTION (6 bits). Similarly, if a function is
performed via the machine’s keyboard, then these bits are set with the INSTRUCTION NO., which 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 (ie. 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.
For a single machine controlled via the serial port, always set M4…M0 = 1, and make sure that the machine itself is
configured as MACHINE NUMBER = 1.
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.
Table 5: Instruction Codes for Protocol 2000
Note: All values in the table are decimal, unless otherwise stated.
INSTRUCTION
DEFINITION FOR SPECIFIC INSTRUCTION
NOTE
#
DESCRIPTION
INPUT
OUTPUT
0
RESET DEVICE
0
0
1
44
SWITCH RELAY DATA
Set equal to control data
input which is to be switched
0=OFF
1=ON
Set equal to control data
output which is to be
switched
2,27
45
REQUEST STATUS OF RELAY
DATA OUTPUT
0
Equal to output number
whose status is reqd
3,4,27