3. A switch will increment a counter on when engaged. This counter can be reset by a second switch. The value in the counter should be multiplied by 5, and then displayed as a binary output using output integer ’O_lights’.
4. Create a ladder logic program that will start when input A is turned on and calculate the series below. The value of n will start at 0 and with each scan of the ladder logic n will increase by 2 until n=20. While the sequence is being incremented, any change in A will be ignored.
6. A thumbwheel input card acquires a four digit BCD count. A sensor detects parts dropping down a chute. When the count matches the BCD value the chute is closed, and a light is turned on until a reset button is pushed. A start button must be pushed to start the part feeding. Develop the ladder logic for this controller. Use a structured design technique such as a state diagram.
13. A machine is being designed for a foreign parts supplier. As part of the contractual agreement the logic will run until February 26, 2008. However, after that date the machine will enable a ‘contract_expired’ value and no longer run. Write the ladder logic.
15. The input bits from ’input_card_A’ are to be read and XORed with the inputs from ’input_card_B’. The result is to be written to the output card ’output_card’. If the binary pattern of the least 16 output bits is 1010 0101 0111 0110 then the output ’match_bell’ will be set. Write the ladder logic.
17. A machine ejects parts into three chutes. Three optical sensors (A, B and C) are positioned in each of the slots to count the parts. The count should start when the reset (R) button is pushed. The count will stop, and an indicator light (L) turned on when the average number of parts counted is 100 or greater.
18. a) Write ladder logic to calculate and store the binary (geometric) sequence in 32 bit integer (DINT) memory starting at n up to n so that n = 1, n = 2, n = 4, n = 16, n = 64, etc. b) Will the program operate as expected?