Heartbeat Messages - Curtis Acuity 1030 Manual

Curtis 1030 Acuity Manual,
The NMT message identifier consists of the standard message type (NMT)
in the top four bits; the bottom seven bits must be set to zero.
The first data byte of the NMT command is the command specifier:
The second byte of the NMT command defines whether this NMT is for
all slaves on the bus (data byte = 00h) or for a specific node (data byte = Node
ID of the Acuity).

Heartbeat messages

The heartbeat message is a very low priority message, periodically sent by each
slave device on the bus. The heartbeat message has a single byte of data and
requires no response. Once the Acuity is in the Pre-Operational state, the next
heartbeat will be issued and will continue until communication is stopped.
The heartbeat message has only one data byte. The top bit is reserved and
should be set to zero. The bottom 7 bits hold the current NMT device state as
defined previously.
Rev. C
4 — CANopen COMMUNICATIONS
Value Command Specifier
01h Enter the Operational state
02h Enter the Stopped
80h Enter the Pre-Operational
81h Reset Acuity (warm
82h Reset the CANbusXx
stateXx
stateXx
boot)Xx
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