Diff: 7SegSRDriver.cpp

Revision:

0:1832d0ed8da8

Child:

2:5f76214d096c

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/7SegSRDriver.cpp	Sun May 01 16:13:00 2011 +0000
@@ -0,0 +1,68 @@
+#include "mbed.h"
+#include "7SegSRDriver.h"
+
+/* mbed 7-Segment Display Driver Library (via an 8bit Shift Register)
+ * Copyright (c) 2011 Paul Law
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+// Display should be hooked up to shift register as follows:
+// Q0 : Decimal Point, Q1-Q7 : Segments a-g
+
+SSegSRDriver::SSegSRDriver(PinName srData, PinName srClock, PinName srLatch, bool disp_type): _srData(srData), _srClock(srClock), _srLatch(srLatch) {
+    _disp_type = disp_type;
+    write_raw(0);
+}
+
+void SSegSRDriver::set_type(bool disp_type) {
+    _disp_type = disp_type;
+}
+
+void SSegSRDriver::clear() {
+    write_raw(0);
+}
+
+void SSegSRDriver::write(unsigned char number) {
+    write(number,0);
+}
+
+void SSegSRDriver::write(unsigned char number, bool dp) {
+    if (number<16) {
+        // Find the definition of the number in chardefs, shift left, set dp (LSB)
+        write_raw((SSegSRDriver_chardefs[number] << 1) | dp);
+    }
+}
+
+void SSegSRDriver::write_raw(unsigned char bValue) {
+
+    if (!_disp_type) bValue = ~bValue;  // Reverse value for Common Anode
+
+    if (bValue<=0xFF) {
+        // Push value to shift register and latch
+        _srLatch = 0;
+        for (int i=7;i>=0;i--) {    // Output MSB to LSB
+            _srClock = 0;
+            _srData = (bValue & (1<<i));
+            _srClock = 1;
+        }
+        _srLatch = 1;
+        _srData = 0;
+    }
+}
\ No newline at end of file