Why reserved BIT in CAN Frame wrong? ATMega16M1

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Hallo i have a homebus system that works fine, because i have with the oscilloscop see that the reserved bit in the CAN frame / telegram is wrong The third bit = 1 in the tripple block bevor the quadra DLC Block. Can anywhos say me whats going wrong. The signal level is inverted. My Microchip CAN Bus Analyzer view me the wrong DLC (17) and no Data. 0b10001 = 17. 

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Wrong or just different then how others have implemented it?

Please post from the CAN spec that says this is "wrong".

 

Jim

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the specs 2.0 from Bosch says

The control field consists of six bits. It includes the DLC and two bits reserved for future expansion (1 = for 29bit ID). The reserved bits have to be sent dominant. Receivers accept  dominant and ressesive bits in all combinations.

 

My ATMega16M1 sends with the MCP2551 CAN Tranceiver an the Microchip PIC18F2680 have the same Tranceiver MCP2551 As I see it, this bit in the PIC is incorrectly added to the DLC.

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kosmoskosmos wrote:
Receivers accept  dominant and ressesive bits in all combinations.
Doesn't that mean that 0 OR 1 is "right" ?

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because why the PIC18F add this Bit to the DLC? He had to ignore this bit or not?

 

Anywhos else working with ATMega16M1 / ATMega32M1 / ATMega64M1 with CAN communication to compare a CAN message?

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kosmoskosmos wrote:
because why the PIC18F add this Bit to the DLC?

You need to ask that question on a PIC forum!

 

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the AVR sends it already wrong, so I thought I'm here for a question. On the software side, I have no influence on it. I will ask in a PIC forum, too.

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Are you accounting for any bit-stuffing that may be happening?