Serial communication method, serial communication device and a serial communication system

摘要

PROBLEM TO BE SOLVED: To allow communication between serial communication devices to be normally performed while a pulse oscillation circuit of each of the serial communication devices uses an inaccurate and inexpensive CR oscillation circuit to reduce cost.SOLUTION: Predetermined several bits in a latter part at or less than the bit number equal to one bit subtracted from the data length of transmission data is transmitted by fixing them to either an L level or H level. This makes it possible to reduce cost by using an inexpensive CR oscillation circuit, and if an oscillation frequency fluctuates significantly, and even if normal sampling is not possible at a stop bit and a data bit near the stop bit, communication can be done normally because predetermined several bits in the latter part can be recognized as the stop bit.