Kramer Electronics VP-411DS Kramer Protocol, Definition For Specific Instruction, Description

Kramer Protocol 2000

4th 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.

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.

Table 7: 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	0	0	1
1	SWITCH INPUT	Set equal to video input	1	2
		which is to be switched
		(0 = disconnect)
5	REQUEST STATUS OF A	0	Equal to output number	3
	VIDEO OUTPUT		whose status is reqd
16	ERROR / BUSY	0	error	4
			invalid instruction
			out of range
			machine busy
			RX buffer overflow
30	LOCK FRONT PANEL	Panel unlocked	0	2
		Panel locked
31	REQUEST WHETHER	0	0	7
	PANEL IS LOCKED
61	IDENTIFY MACHINE	video machine name	Request first 4 digits	5
		video software version	Request first suffix
62	DEFINE MACHINE	number of inputs	for video	6
		number of outputs	for audio

NOTES on the above table:

NOTE 1 - When the master switcher is reset, (e.g. when it is turned on), the reset code is sent to the PC. If this code is sent to the switchers, it will reset according to the present power-down settings.

NOTE 2 - These are bi-directional definitions. That is, if the switcher receives the code, it will perform the instruction; and if the instruction is performed (due to a keystroke operation on the front panel), then these codes are sent. For example, if the HEX code

01 85 88 83

was sent from the PC, then the switcher (machine 3) will switch input 5 to output 8. If the user switched input 1 to output 7 via the front panel keypad, then the switcher will send HEX codes:

41	81	87	83
to the PC.

When the PC sends one of the commands in this group to the switcher, then, if the instruction is valid, the switcher replies by sending to the PC the same four bytes that it was sent (except for the first byte, where the DESTINATION bit is set high).

NOTE 3 - The reply to a "REQUEST" instruction is as follows: the same instruction and INPUT codes as were sent are returned, and the OUTPUT is assigned the value of the requested parameter. The replies to instructions 10 and 11 are as per the definitions in instructions 7 and 8 respectively. For example, if the present status of machine number 5 is breakaway setting, then the reply to the HEX code

0B	80	80	85
would be HEX codes
4B	80	81	85

NOTE 4 - An error code is returned to the PC if an invalid instruction code was sent to the switcher, or if a parameter associated with the instruction is out of range (e.g. trying to save to a setup greater than the highest one, or trying to switch an input or output greater than the highest one defined). This code is also returned to the PC if an RS-232 instruction is sent while the machine is being programmed via the front panel. Reception of this code by the switcher is not valid.

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