I don't have an oscilloscope, all I have is a digital volt meter. Using the volt meter all I see is 2.5 Volts. I will try to get an oscillosc= ope and see if there is something sent on the wire. Both nodes run at same baud, same PIC24 and almost the same software (a min= or change in one of the nodes to keep sending the messages). --- On Tue, 12/14/10, alan.b.pearce@stfc.ac.uk w= rote: From: alan.b.pearce@stfc.ac.uk Subject: RE: [PIC] PIC24 CAN To: piclist@MIT.EDU Date: Tuesday, December 14, 2010, 4:07 PM > What's odd is that I'm using DMA and the TX buffer interrupt flag is never set. On the Transmit end? I haven't played with CAN, so assume this interrupt should be set when the buffer has been transmitted - presumably with an appropriate acknowledgement. If this is the case then not getting an acknowledgement is a likely cause. If there is no acknowledgement, are both nodes working at the same baud rate ?? But as Olin says, some basic test equipment to see what happens on the data lines is required. --=20 Scanned by iCritical. --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .