| 摘要 |
PURPOSE:To perform the tests of all circuits in a short time just with a single operation by carrying out confirmation of presence/absence of picture signals and automatic self-diagnosis tests successively for each circuit by a prescribed start instruction. CONSTITUTION:An automatic test mode signal S3 is turned on by a start instruction at an operation display part 50 and at the same time a count-up signal is applied to an address counter 80 via an OR gate OR. The signals received from the counter 80 are converted into the designated data by a self-diagnosis ROM 90 and given to a code converting ROM 60 through selectors SEL 4 and 3 for execution of tests. When transmission is through with a single telegram, a deciding circuit 40 of a receiving part A uses a signal showing the end of processing as a start instruction of the part 50 again and then as the count-up signal of the counter 80. Thus the address of the ROM 90 changes and the next telegram is transmitted. Hereafter this operation is repeated to perform automatic tests of all circuits. Furthermore the presence/absence of a picture signal S4 can be visually recognized for each circuit at the part 50 as well as by a host control device and the part A. |
