User manual
KRAMER: SIMPLE CREATIVE TECHNOLOGY 
Kramer Protocol 2000 
18 
11  Kramer Protocol 2000 
The VS-44H is compatible with Kramer’s Protocol 2000
1
 (version 0.50) 
(below)
2
Table 5: Protocol Definitions 
. This RS-232/RS-485 communication protocol uses four bytes of 
information as defined below. The default data rate is 9600 baud, with no 
parity, 8 data bits and 1 stop bit. 
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 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. 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. 
1  The instruction codes in Table 5  are a sub-set of the Protocol 2000. You can find the full protocol on our Web site at 
http://www.kramerelectronics.com  
2 You can download our user-friendly “Software for Calculating Hex Codes for Protocol 2000” from the technical support 
section on our Web site at: http://www.kramerelectronics.com










