Issue Number: 3
29
TELEGRAM 4
The fourth telegram from the master acts as the indication to the slave
node to send the data high byte from the requested parameter. The
data byte is not used in this telegram and should be set to 0.
Bit b15-b12 b11-b8 b7-b4 b3-b0
Value
1XXX 0100 XXXX XXXX
Data word = 0x8400
Stamp number = 4
When the fourth telegram has been received and processed in the
slave node, the node will mirror the stamp number in the non-cyclic IN
word, and load the low byte of the parameter value into the data byte.
Bit b15-b12 b11-b8 b7-b4 b3-b0
Value
1XXX 0100 1101 1100
Data word = 0x84DC
Stamp number = 4
Data low byte = 0xDC
Speed feedback
= (high data byte * 256) + low data byte
= (0x05 * 0x100) + 0xDC
=
0x05DC
=
1500
rpm
6.1.2
Writing parameters using Mode 1
To write to parameters using the non-cyclic channel, the following
telegrams must be sent on each network cycle to construct the final
message.
•
Telegram 1
Define menu number.
•
Telegram 2
Define parameter number.
•
Telegram 3
Set data high byte.
•
Telegram 4
Set data low byte.
Start
Send first telegram
to OUT word 0
Read IN
word 0
Tx_Stamp_No =
R x _ S t a m p _ N o ?
Send next
telegram to
OUT word 0
Tx_Stamp_No
= 4?
N o
Yes
N o
Yes
Check status
of ERR bit
1
E R R O R
Check paramter
exists, and that it is
a Read/Write
parameter
Parameter
written OK
E N D O F
S E Q U E N C E
W R I T E
