BUILT_IN_LOGIC_PROBE

Published:2009/7/2 21:58:00 Author:May | From:SeekIC

PROBE-Permanently wired LEDs indicate TTL levels and changes in levels, LEVEL LED-1 comes on for TTL 1 input and goes out for TTL 0 input. EDGE LED-2 comes on momentarily for input changes. Will detect levels, steps, single pulses, and pulse trains. Only haif of each IC is used, so dual tester can be made if desired. ICs 1a and 1b form noninverting driver for 9602 mono which is triggered on both positive-going and negative-going edges by C1 and D1. Pulse train input having period less than width of flash pulse will keep EDGE indicator on.-K. W. Christner, The Built-In Logic Tester, BYTE, Jan. 1977, p 82-83.



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