Steven Kay / Latch_FET_Driver

Driver to control a peripheral circuit being controlled by the operation of a FET. Inbetween the mbed and FET is a single D type latch, used to latch a signal to the driver.

Latch_FET_Driver.cpp@6:073ee2fd1245, 2016-03-04 (annotated)

Committer:
sk398
Date:
Fri Mar 04 17:53:29 2016 +0000
Revision:
6:073ee2fd1245
Parent:
5:7d1b124490ed 
added method to change state based on given input; outputLow and High shifted to private members

Who changed what in which revision?

UserRevisionLine numberNew contents of line
sk398 0:87f2d094bea3 1 #include "mbed.h"
sk398 0:87f2d094bea3 2 #include "Latch_FET_Driver.h"
sk398 0:87f2d094bea3 3
sk398 5:7d1b124490ed 4
sk398 5:7d1b124490ed 5 /* =============================================================
sk398 5:7d1b124490ed 6 Latch_FET_Driver constructor
sk398 5:7d1b124490ed 7
sk398 5:7d1b124490ed 8 Inputs
sk398 5:7d1b124490ed 9 ------
sk398 5:7d1b124490ed 10 PinName D: Pin to create D input to D Latch
sk398 5:7d1b124490ed 11 PinName CLK: Pin to create CLK input to D Latch
sk398 5:7d1b124490ed 12
sk398 5:7d1b124490ed 13 Description
sk398 5:7d1b124490ed 14 -----------
sk398 5:7d1b124490ed 15
sk398 5:7d1b124490ed 16 Once the new DigitalOut types are assigned, the D Latch at
sk398 5:7d1b124490ed 17 the given Pins is initialised to an outputLow state, ensuring
sk398 5:7d1b124490ed 18 that uopn setup, a known state is entered quickly.
sk398 5:7d1b124490ed 19
sk398 5:7d1b124490ed 20 ============================================================= */
sk398 5:7d1b124490ed 21 Latch_FET_Driver::Latch_FET_Driver(PinName D,PinName CLK)
sk398 0:87f2d094bea3 22 {
sk398 5:7d1b124490ed 23 // Assign passed in Pin Names as new DigitalOut data types
sk398 5:7d1b124490ed 24 _D = new DigitalOut(D);
sk398 5:7d1b124490ed 25 _CLK = new DigitalOut(CLK);
sk398 5:7d1b124490ed 26
sk398 5:7d1b124490ed 27 // Ensure that D latch does not enter unknown state
sk398 5:7d1b124490ed 28 // Initialise is the same as the outputLow method
sk398 5:7d1b124490ed 29 Latch_FET_Driver::outputLow();
sk398 0:87f2d094bea3 30 }
sk398 0:87f2d094bea3 31
sk398 6:073ee2fd1245 32 void Latch_FET_Driver::changeOutputState(bool stateChange)
sk398 6:073ee2fd1245 33 {
sk398 6:073ee2fd1245 34 if(stateChange == HIGH)
sk398 6:073ee2fd1245 35 {
sk398 6:073ee2fd1245 36 Latch_FET_Driver::outputHigh();
sk398 6:073ee2fd1245 37 }
sk398 6:073ee2fd1245 38 else
sk398 6:073ee2fd1245 39 {
sk398 6:073ee2fd1245 40 Latch_FET_Driver::outputLow();
sk398 6:073ee2fd1245 41 }
sk398 6:073ee2fd1245 42 }
sk398 6:073ee2fd1245 43
sk398 5:7d1b124490ed 44 /* ================================================================
sk398 5:7d1b124490ed 45 outputHigh is a public method to set a HIGH output on the given
sk398 5:7d1b124490ed 46 D Latch.
sk398 5:7d1b124490ed 47
sk398 5:7d1b124490ed 48 The procedure to set Q into a HIGH condition is as follows;
sk398 5:7d1b124490ed 49
sk398 5:7d1b124490ed 50 1. Ensure CLK is low
sk398 5:7d1b124490ed 51 2. Set D high
sk398 5:7d1b124490ed 52 3. wait STATE_DELAY us
sk398 5:7d1b124490ed 53 4. Set CLK high
sk398 5:7d1b124490ed 54 5. wait 10*STATE_DELAY us
sk398 5:7d1b124490ed 55 6. Set CLK low
sk398 5:7d1b124490ed 56 7. wait STATE_DELAY us
sk398 5:7d1b124490ed 57 8. set D low
sk398 5:7d1b124490ed 58 9. return void
sk398 5:7d1b124490ed 59 ================================================================ */
sk398 5:7d1b124490ed 60 void Latch_FET_Driver::outputHigh()
sk398 0:87f2d094bea3 61 {
sk398 5:7d1b124490ed 62 _CLK -> write(LOW);
sk398 5:7d1b124490ed 63 _D -> write(HIGH);
sk398 5:7d1b124490ed 64 wait_us(STATE_DELAY);
sk398 5:7d1b124490ed 65 _CLK -> write(HIGH);
sk398 5:7d1b124490ed 66 wait_us(10*STATE_DELAY);
sk398 5:7d1b124490ed 67 _CLK -> write(LOW);
sk398 5:7d1b124490ed 68 wait_us(STATE_DELAY);
sk398 5:7d1b124490ed 69 _D -> write(LOW);
sk398 0:87f2d094bea3 70 }
sk398 0:87f2d094bea3 71
sk398 5:7d1b124490ed 72 /* ================================================================
sk398 5:7d1b124490ed 73 outputLow is a public method to set a HIGH output on the given
sk398 5:7d1b124490ed 74 D Latch.
sk398 5:7d1b124490ed 75
sk398 5:7d1b124490ed 76 The procedure to set Q into a LOW condition is as follows;
sk398 5:7d1b124490ed 77
sk398 5:7d1b124490ed 78 1. Ensure CLK is low
sk398 5:7d1b124490ed 79 2. Set D low
sk398 5:7d1b124490ed 80 3. wait STATE_DELAY us
sk398 5:7d1b124490ed 81 4. Set CLK high
sk398 5:7d1b124490ed 82 5. wait 10*STATE_DELAY us
sk398 5:7d1b124490ed 83 6. Set CLK low
sk398 5:7d1b124490ed 84 7. wait STATE_DELAY us
sk398 5:7d1b124490ed 85 8. return void
sk398 5:7d1b124490ed 86 ================================================================ */
sk398 5:7d1b124490ed 87 void Latch_FET_Driver::outputLow()
sk398 5:7d1b124490ed 88 {
sk398 5:7d1b124490ed 89 _CLK -> write(LOW);
sk398 5:7d1b124490ed 90 _D -> write(LOW);
sk398 5:7d1b124490ed 91 wait_us(STATE_DELAY);
sk398 5:7d1b124490ed 92 _CLK -> write(HIGH);
sk398 5:7d1b124490ed 93 wait_us(10*STATE_DELAY);
sk398 5:7d1b124490ed 94 _CLK -> write(LOW);
sk398 5:7d1b124490ed 95 wait_us(STATE_DELAY);
sk398 5:7d1b124490ed 96 }
sk398 2:9059b675917e 97
sk398 5:7d1b124490ed 98