APC 6000 user manual Function 11 reading event counters, Function 15 writing n consecutive bits

JBUS protocol (continued)

Function 11: reading event counters

The master and each slave have one event counter.

This counter is incremented each time a frame is received and interpreted correctly by the slave (except for function 11 itself).

A correctly transmitted message increments the counter. If the slave sends an exception response, the counter is not incremented.

The master can read the counter to determine whether or not the slave correctly interpreted the command (incremented the counter or not).

These functions can be used to diagnose the data exchange taking place between master and slaves.

	request
	slave address	0B	CRC 16
	response
	slave address	0B	0	slave	CRC 16
				counter word
	1 byte	1 byte	2 bytes	2 bytes	2 bytes
If the master counter equals the				If the master counter is one higher
slave counter, the slave executed				than the slave counter, the slave
the command sent by the master.				did not execute the command sent
				by the master.

Function 15: writing n consecutive bits

request

slave adress

0F

address of the first bit

number of bits

number of bytes

bit data

CRC 16

1 byte	1 byte 2 bytes		2 bytes		1 byte	n bytes	2 bytes
réponse		2 X 1968
				1 N 246

last bit of		first bit of	last bit of	first bit of
first byte		first byte	byte N	byte N
	first byte			N bytes
response

slave address

0F

address of the first bit

number of bits

CRC 16

1 byte	1 byte	2 bytes	2 bytes	2 bytes
		1	X 1968

Note: if the slave address is 0, all units execute the write command without sending a response.

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