| 摘要 |
PURPOSE:To attain easly data transmission between microprocessors by requesting transmission when an idle two-way data line connected between the microprocessors is detected. CONSTITUTION:When the microprocessor muPC I 12 detects that a strobe II line 15 is at H level, the level of a strobe I line 14 is decreased. When the muPCII13 detects the decrease in the level of the line 14, the muPCII13 informs the reception state to the muPC12 by decreasing the level of the line 15, the muPC12 detects the level fall of the line 15 and recognizes the reception state of the muPC13, transmission data is outputted to a two-way data lin 16 and the level of the 14 is increased at the same time. The muPC13 recognizes the output of the transmission data to the line 16 by detecting the level increase of the line 14 and after the transmission data is read, the level of the line 15 is increased. The muPC12 detects the level increase of the line 15 after the data read is finished and opens the line 16. |
