Matt circuit

Description  The bi-directional sequencer uses a 4 bit binary up/down counter (CD4516) and two "1 of 8 line decoders" (74HC138 or 74HCT138) to generate the popular "Night Rider" display. A Schmitt Trigger oscillator provides the clock signal for the counter and the rate can be adjusted with the 500K pot. Two additional Schmitt Trigger inverters are used as a SET/RESET latch to control the counting direction (up or down). Be sure to use the 74HC14 and not the 74HCT14, the 74HCT14 may not work due to the low TTL input trigger level. When the highest count is reached (1111) the low output at pin 7 sets the latch so that the UP/DOWN input to the counter goes low and causes the counter to begin decrementing. When the lowest count is reached (0000) the latch is reset (high) so that the counter will begin incrementing on the next rising clock edge. The three lowest counter bits (Q0, Q1, Q2) are connected to both decoders in parallel and the highest bit Q3 is used to select...

Basic PLC Ladder Programming Examples 16 Basic PLC Ladder Programming Training Examples for Beginners.  Hi friends here we are starting here a series of Free Training on PLC Ladder Programming training & tutorials.These PLC Ladder Programs are important to get basics of Ladder programs.   PLC Ladder Practice Problem:  When Start Push Button is Pressed the Motor will turn ON .When Start Push Button is Released Motor will Remain Turn ON When Stop Push Button is Pressed will Turn OFF. If Motor will Not Turn on if Error Signal from Motor Comes. IF Motor is off and Test Push Button is Pressed then Motor will Remain on , If Test Push Button is Released Motor Will Turn OFF (Inch Operation).     Topics Covered in this example is  Conditional Contacts ,SCAN Cycle Ladder Program.         Number of PLC Inputs Required X0 – START pushbutton to Start Motor X1 – STOP pushbutton to Stop Motor X2 – TEST Push Button to Test Motor ...