Most protocol tutorials show the correct sequence. These lessons show the failures, and give the check that finds each one. The labs operate in the browser. You need no hardware and no oscilloscope.
The serial buses used in most embedded products, and the failures that each bus causes without an error message. Each lesson gives the check that finds the failure, and a lab that operates in the browser.
Two wires, one shared bus, and every device can only pull down. This lesson gives the four failures that occur most often — missing pull-up resistors, address conflicts, clock stretching, and incorrect probe connections — and the check that finds each one.
Lesson 1 · ~14 min
Incorrect clock polarity and phase, chip-select errors, a slave device that continues to drive MISO, and the clock frequency at which the bus stops.
Coming soon · ~12 min
A filter that discards every frame without a message, the bit timing that sets the controller to the bus-off state, and an ISO-TP flow control failure from real hardware.
Coming soon · ~14 min
TX and RX connected incorrectly, logic levels that do not agree, and the receiver overrun that discards bytes while the system looks correct.
Coming soon · ~10 min
1 lesson published. Want one on a bus we have not covered? Ask on r/labwired.