| 摘要 |
PURPOSE:To attain the miniaturization and low cost of equipment by using software of a microcomputer to realize bit synchronizing functions in a data transmission system requiring a bit synchronizing circuit to integrate a microcomputer to other microcomputers for communication control. CONSTITUTION:A clock circuit 2 generates the same frequency for the transmission/reception and a counter circuit 3 uses the signal to attain counting. When a edge in an input signal 10 is detected by an edge detection circuit 1, an edge detection signal 11 is generated and a counting value from a counter circuit 3 is latched as edge data by a latch circuit 4, and a transfer circuit 5 transfers the latched edge data to a memory circuit 6. An arithmetic circuit 7 obtains the means error and data sampling point of the internal reference edge from the count of the memory circuit 6 and when the error of a reference edge is larger than a specified value, a reset signal is generated by a reset circuit 8 to restore all other circuits to the initial state. Moreover, a data sampling point (count) and a count of the counter circuit 3 are compared and when they are coincident, a sampling signal is generated by a comparator circuit 9. |
