Titan Electronics USB-2CAN-M, Руководство пользователя

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8.3.10 Setting Acceptance Mask
The acceptance mask, in conjunction with the acceptance code (M), defines which
CAN message frames (i.e. of a specific ID or range of CAN IDs) will be passed to the
serial interface. The acceptance mask value corresponds to bits within a range of valid
CAN IDs for either standard or extended CAN frames. This command is only active if
the CAN channel is initiated and not opened.
Set Acceptance Mask (m) command should be executed prior to Set Acceptance Code
(M).
Note : The CAN channel will revert to its prior state after execution. For example, if the
channel is open when this command is executed, the channel will update the setting
and return to the open state.
Command Response Function
miii[CR]
[CR]
Set acceptance mask for standard CAN frame (11
bit) identifier
miiiiiiii[CR] [CR]
Set acceptance mask for extended CAN frame (29
bit) identifier
iii = standard 11-bit CAN mask (0x000 through 0x7FF)
iiiiiiii = extended 29-bit CAN mask (0x00000000 through 0x1FFFFFFF)
A value of “0” in a bit location indicates that the bit location ID value is to be ignored
when filtering messages.
Default is to pass all frames (acceptance mask = 0x000 for standard messages and
0x00000000 for extended messages)
Example: m700[CR] set acceptance mask to check bits 10, 9 and 8 against the filter.
Bits 7 through 0 are ignored as “don’t care”. Use the acceptance mask in conjunction
with the acceptance code, which is explained next.