Library to use 595 shift registers

Files at this revision

API Documentation at this revision

Comitter:
henryeherman
Date:
Wed Oct 30 18:15:52 2013 +0000
Commit message:
Shift register for driving chip select lines on Elixys Synthesizer board

Changed in this revision

ShiftRegister.cpp Show annotated file Show diff for this revision Revisions of this file
ShiftRegister.h Show annotated file Show diff for this revision Revisions of this file
diff -r 000000000000 -r 46b1b63c40e6 ShiftRegister.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ShiftRegister.cpp	Wed Oct 30 18:15:52 2013 +0000
@@ -0,0 +1,34 @@
+#include "mbed.h"
+#include "ShiftRegister.h"
+
+using namespace mbed;
+
+ShiftRegister::ShiftRegister(DigitalOut &clk, DigitalOut &dat, 
+                DigitalOut &latch, DigitalOut &clr, 
+                DigitalOut &oe): _clk(clk), _dat(dat),
+                                    _latch(latch), _clr(clr),
+                                    _oe(oe) {
+                                    
+    _clk = 1;
+    _dat = 1;
+    _clr = 0;
+    _oe = 1;     
+    _clr = 1;
+    _oe = 0;   
+}
+
+ShiftRegister::~ShiftRegister() {
+    // Nothing to do!
+    clear();
+}
+
+
+
+void ShiftRegister::clear() {
+    _clk = 1;
+    _dat = 1;
+    _clr = 0;
+    _oe = 1;     
+    _clr = 1;
+    _oe = 0;  
+}
\ No newline at end of file
diff -r 000000000000 -r 46b1b63c40e6 ShiftRegister.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ShiftRegister.h	Wed Oct 30 18:15:52 2013 +0000
@@ -0,0 +1,56 @@
+#include "mbed.h"
+#ifndef SHIFTREGISTER_H
+#define SHIFTREGISTER_H
+
+
+class ShiftRegister {
+
+public:
+
+/*
+* Constructor
+*/
+ShiftRegister(DigitalOut &clk, DigitalOut &dat, 
+                DigitalOut &latch, DigitalOut &clr, 
+                DigitalOut &oe);
+
+/*
+* Destructor
+*/
+~ShiftRegister();
+
+/*
+* Write Value
+*/
+template <typename T>
+int write(T val, int bits);
+
+void clear();
+
+private:
+DigitalOut &_clk;
+DigitalOut &_dat;
+DigitalOut &_latch;
+DigitalOut &_clr;
+DigitalOut &_oe;
+
+}; // end class ShiftRegister
+
+
+template <typename T>
+int ShiftRegister::write(T val, int bits) {        
+    T tmpval = ~0;
+    int tmpsz = sizeof(val)*8;
+    val = tmpval & val;  
+    bits = tmpsz < bits ? tmpsz : bits;
+    for(char i = 0; i < bits; i++) {
+        _dat.write((val >> i) & 0x01);        
+        _clk = 0;        
+        _clk = 1;
+    }
+    _latch = 0; 
+    _latch =1;
+    return val;
+}
+
+#endif //ShiftRegister
\ No newline at end of file