Hello Thorsten,

I need to know the maximal length of a message sent. The SmartPointer class says one payload can maximal be 252byte. Is this the maximal Message size?

Depends on the backend you are using. The standard CAN backend is limited to 8 CAN messages per xpcc message. This results in a maximal length of 6*8 = 48 byte. This can be extended with a different backend, but that is up to you. The next limited is the mentioned smart pointer. The limited there can be increased for >= 8 bit processors or through the use of platform specific synchronization mechanisms. At the moment it avoids explicit atomic operations by operating on a variable size (=8 bit) which can be read atomically by all microprocessors.

Fabian

Hi,

as far as I can see it it makes no sense to use messages, which are bigger than 48byte then, because we try to send the same messages on all

platforms.

I wouldn't impose an arbitrary length limit for other backends (if this is about the TCP/IP backend). I am sure the TIPC Backend doesn't have the 48 byte limit, that was just a design decision to keep the memory footprint of the message management low for AVR microcontroller when using the CAN backend.

Fabian