I appreciate that but, especially with this issue, we need to be as precise and accurate as possible.
Yeah, I can see that. Could I suggest that you ask here before believing the hype?
Where are you seeing that 1Mb CAN becomes overloaded with reading an accelerometer with steppers operating? In general, there is lots of bandwidth available for operating the printer and the only case where steppers are being used with an accelerometer is when you are doing resonance testing which does not generate a lot of timing signals for the steppers.
It is EXTREMELY difficult to compare the data bandwidth between communications protocols. Bi-directional communications paths rarely provide any kind of significant speed advantage in applications because most messages can be characterized as COMMAND-WAIT_FOR_ACK which means that there is no advantage to having a bi-directional communications medium. RS-232 has at least a 20% overhead, assuming 8-N-1 which is the most common byte formatting, and is probably more with the actual commands/data/acks going back and forth. It’s possible that NRZ serial at 250kbps is faster than 1Mbps CAN but I would want to see the analysis along with assumptions before stating that either approach is faster.
Could I ask that you don’t buy this board, unless you absolutely need to get things running? The H36 Combo uses an STM32 as its MCU and an ADXL345 as its accelerometer. From what I understand, that combination is running fine and bringing it in can add to the confusion.