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pazi88 / STM32_CAN

CAN bus Library for Arduino STM32
GNU General Public License v3.0
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Filter logic is wrong #30

Closed ppcd9220 closed 5 months ago

ppcd9220 commented 5 months ago

When setting filters there is no way to set it for Standard or Extended ID.

What type of messages to filter is defined here: ` if (filter_id <= 0x7FF) { // Standard ID can be only 11 bits long

}` This is completely wrong logic: If the ID less than 0x7FF - Standard ID, otherwise - EXT.

i.e Message with ID= 0x01 Could be both EXT and Standard. But with current approach all messages less than 0x7FF and EXT ID flag active is not possible to pass the filter.

pazi88 commented 5 months ago

hmmnn, yeah. Need to fix that.

ppcd9220 commented 5 months ago

hmmnn, yeah. Need to fix that. Maybe just add a flag: EXT_ID ?

pazi88 commented 5 months ago

hmmnn, yeah. Need to fix that. Maybe just add a flag: EXT_ID ?

Looks like that's the thing I need to do. At least for me it looks like that you need to specify that is the ID standard or extended. I can't seem to make it accept both. So I'll add a flag to set that.

ppcd9220 commented 5 months ago

hmmnn, yeah. Need to fix that. Maybe just add a flag: EXT_ID ?

Looks like that's the thing I need to do. At least for me it looks like that you need to specify that is the ID standard or extended. I can't seem to make it accept both. So I'll add a flag to set that.

Yes. If you need to accept both - you can setup 2 different filters: one for standard and one for EXT. This flag (Ext_ID) in CAN_ID completely separates address spaces for Standard and Extended. And they don't cross or interact. That's why it is absolutely safe to work at the same time with Can_Open messages/devices that are using 11-bit standard addressing and J1939 that uses EXT (29-bit) IDs

ppcd9220 commented 5 months ago

So I'll add a flag to set that.

Thank you Very Much for your Work on this lib!