How To Set The Acceptance Code And Mask - ICP DAS USA I-7540D User Manual

3.1.4

How to set the Acceptance Code and Mask

Acceptance Code (AccCode): The CAN ID bits that you want to get.
Acceptance Mask (AccMask): The CAN ID bits that you want to filter.
The AccCode is used for deciding what kind of ID the CAN controller will accept.
The AccMask is used for deciding which bit of ID will need to check with AccCode.
If the bit of AccMask is set to 0, it means that the bit in the same position of ID
need to be checked, and that ID bit value needs to match the bit of AccCode in the
same position.
For 11-bit ID Message:
AccCode and AccMask
AccCode[0] and AccMask[0]
AccCode[1] and AccMask[1]
AccCode[1] and AccMask[1]
AccCode[1] and AccMask[1]
AccCode[2] and AccMask[2]
AccCode[3] and AccMask[3]
For 29-bit ID Message:
AccCode and AccMask
AccCode[0] and AccMask[0]
AccCode[1] and AccMask[1]
AccCode[2] and AccMask[2]
AccCode[3] and AccMask[3]
AccCode[3] and AccMask[3]
AccCode[3] and AccMask[3]
I-7540D CAN-Ethernet Gateway User's Manual (Version 1.8, March/2021)
Bit Position
bit7~bit0
bit7~bit5
bit4
bit3~bit0
bit7~bit0 bit7 ~ bit0 of 1st byte data
bit7~bit0 bit7 ~ bit0 of 2nd byte data
Bit Position
bit7~bit0
bit7~bit0
bit7~bit0
bit7~bit3
bit2
bit1~bit0
Filter Target
bit10 ~ bit3 of ID
bit2 ~ bit0 of ID
RTR
no use
Filter Target
bit28~ bit21 of ID
bit20 ~ bit13 of ID
bit12 ~ bit5 of ID
bit4 ~ bit0 of ID
RTR
no use
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