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6.3.5. CAN Parameters
The CAN communication settings are shown in Figure 5.5. Options are available to set the base
message ID number may be selected, and the offset from this base number for the reception of user
commands over CAN, and whether an acknowledgement of these user commands is sent on the next
higher message number. Data may be transmitted on either multiple messages, or alternatively on a
single message ID, with a selectable delay between messages. Additionally the CAN bus baudrate
and sample point can be modified via the setting of the BRP, TSEG1, TSEG2 & SJW registers.
Figure 5.5, CAN Comms group
‘CAN First TX Message ID’
flightDAQ uses standard CAN message arbitration id’s, and the unit is assigned the
most significant 2 digits of the Hex base address. For the digits 0x1A for example,
data for the first 4 channels will be sent on 0x1A0, the next 4 on 0x1A1, etc.
Message scheme/delay
Select ‘Multiple Messages’ for the 4 channels per message, multiple message
scheme. Alternatively, data may be packed 3 channels per m identifier byte,
with a selectable delay between messages.
‘CAN RX ID Offset’
Selects the hex offset from the base message ID where flightDAQ will receive
incoming user commands (see user command document). If ‘Ack. Enabled’ is
selected, the unit will acknowledge the reception of a correctly formatted command on
the message ID calculated as Base ID + RX 1
‘Apply’
Applies the settings to the local settings memory
Table 5.5, CAN Comms group settings.