4180Lab1Part3
Fork of MCP23S17_Basic_IO_Demo by
Revision 3:3081585fbce1, committed 2017-02-27
- Comitter:
- CRaslawski
- Date:
- Mon Feb 27 22:31:04 2017 +0000
- Parent:
- 2:934a0500abde
- Commit message:
- initial commit
Changed in this revision
| main.cpp | Show diff for this revision Revisions of this file |
| part3.cpp | Show annotated file Show diff for this revision Revisions of this file |
--- a/main.cpp Fri Jan 28 02:04:05 2011 +0000
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,66 +0,0 @@
-// A simple IO demo using the MCP23S17 library
-//
-// MCP23S17 Library Copyright (c) 2010 Romilly Cocking
-// Released under the MIT License: http://mbed.org/license/mit
-//
-// See http://mbed.org/users/romilly/notebook/mcp23s17-addressable-16-bit-io-expander-with-spi/
-//
-//
-// MCP23S17 datasheet http://ww1.microchip.com/downloads/en/DeviceDoc/21952b.pdf
-// uses MCP23S17 library version 0.4
-
-#include "mbed.h"
-#include "MCP23S17.h"
-// Create SPI bus
-SPI spi(p5, p6, p7);
-//
-// Wiring Connections:
-// mbed p5,p6,p7 are tied to MCP23S17 SI, SO, SCK pins
-// mbed p20 to MCP23S17 CS
-// MCP23S17 reset pin pulled high
-// MCP23S17 GPA0 connected to GPB0 for loopback test
-// A0, A1, A2 of the MCP23S17 are tied to ground on the breadboard, so the 8-bit address for writes is 0x40
-// This is referred to as the opcode in the device datasheet
-char Opcode = 0x40;
-
-// Next create a MCP23S17
-// mbed p20 is connected to ~chipSelect on the MCP23S17
-MCP23S17 chip = MCP23S17(spi, p20, Opcode);
-
-// Optional software reset - mbed p14 to MCP23S17 reset pin
-// DigitalOut reset(p14);
-
-DigitalOut led1(LED1); // mbed LED1 is used for test status display
-
-int main() {
-// The MCP23S17 reset pin can just be pulled high, since it has a power on reset circuit.
-// The reset pin can be used for a software forced reset by pulling it low with an mbed GPIO pin.
-// But just leave it pulled high for this simple demo code.
-// After a power on reset, both IO ports default to input mode
-//
-// Here is the optional code for a software reset
-// reset = 0;
-// wait_us(1);
-// reset = 1;
-//
-// Set all 8 Port A bits to output direction
- chip.direction(PORT_A, 0x00);
-// Set all 8 Port B bits to input direction
- chip.direction(PORT_B, 0xFF);
- led1=0;
-// Start Loopback test sending out and reading back values
-// loopback test uses A0 and B0 pins - so use a wire to jumper those two pins on MCP23S17 together
- while (1) {
- // write 0xAA to MCP23S17 Port A
- chip.write(PORT_A, 0xAA);
- wait(.5);
- // read back value from MCP23S17 Port B and display B0 on mbed led1
- led1 = chip.read(PORT_B)& 0x01;
- // write 0x55 to MCP23S17 Port A
- chip.write(PORT_A, 0x55);
- wait(.5);
- // read back value from MCP23S17 Port B and display B0 on mbed led1
- led1 = chip.read(PORT_B)& 0x01;
- // led1 should blink slowly when it is all working
- }
-}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/part3.cpp Mon Feb 27 22:31:04 2017 +0000
@@ -0,0 +1,93 @@
+// A simple IO demo using the MCP23S17 library
+//
+// MCP23S17 Library Copyright (c) 2010 Romilly Cocking
+// Released under the MIT License: http://mbed.org/license/mit
+//
+// See http://mbed.org/users/romilly/notebook/mcp23s17-addressable-16-bit-io-expander-with-spi/
+//
+//
+// MCP23S17 datasheet http://ww1.microchip.com/downloads/en/DeviceDoc/21952b.pdf
+// uses MCP23S17 library version 0.4
+
+#include "mbed.h"
+#include "MCP23S17.h"
+// Create SPI bus
+SPI spi(p11, p12, p13);
+//
+// Wiring Connections:
+// mbed p5,p6,p7 are tied to MCP23S17 SI, SO, SCK pins
+// mbed p20 to MCP23S17 CS
+// MCP23S17 reset pin pulled high
+// MCP23S17 GPA0 connected to GPB0 for loopback test
+// A0, A1, A2 of the MCP23S17 are tied to ground on the breadboard, so the 8-bit address for writes is 0x40
+// This is referred to as the opcode in the device datasheet
+char Opcode = 0x40;
+
+// Next create a MCP23S17
+// mbed p20 is connected to ~chipSelect on the MCP23S17
+MCP23S17 chip = MCP23S17(spi, p20, Opcode);
+
+// Optional software reset - mbed p14 to MCP23S17 reset pin
+// DigitalOut reset(p14);
+
+DigitalOut led1(LED1); // mbed LED1 is used for test status display
+
+int main()
+{
+// The MCP23S17 reset pin can just be pulled high, since it has a power on reset circuit.
+// The reset pin can be used for a software forced reset by pulling it low with an mbed GPIO pin.
+// But just leave it pulled high for this simple demo code.
+// After a power on reset, both IO ports default to input mode
+//
+// Here is the optional code for a software reset
+// reset = 0;
+// wait_us(1);
+// reset = 1;
+//
+// Set all 8 Port A bits to output direction
+ chip.direction(PORT_A, 0x00);
+// Set all 8 Port B bits to input direction
+ chip.direction(PORT_B, 0xFF);
+ led1=0;
+// Start Loopback test sending out and reading back values
+// loopback test uses A0 and B0 pins - so use a wire to jumper those two pins on MCP23S17 together
+
+ /*
+ while (1) {
+ // write 0xAA to MCP23S17 Port A
+ chip.write(PORT_A, 0xAA);
+ wait(.5);
+ // read back value from MCP23S17 Port B and display B0 on mbed led1
+ led1 = chip.read(PORT_B)& 0x01;
+ // write 0x55 to MCP23S17 Port A
+ chip.write(PORT_A, 0x55);
+ wait(.5);
+ // read back value from MCP23S17 Port B and display B0 on mbed led1
+ led1 = chip.read(PORT_B)& 0x01;
+ // led1 should blink slowly when it is all working
+ }
+ */
+ //run while loop to check if button has been pushed down
+ //read port B for 0x01
+ bool ledOn = false;
+ while(1) {
+ //wait(0.5);
+ if( chip.read(PORT_B)&0x01 ){ //if button is pushed down, light LED
+ //wait();
+ if(ledOn) { //if on, turn led off
+ chip.write(PORT_A, 0x00);
+ ledOn = false;
+ }
+ else { //if led off, turn on.
+ chip.write(PORT_A, 0x01); // write 1 to LED pin, turning it on
+ ledOn = true;
+ }
+ }
+ wait(.2);
+ //else{
+ // chip.write(PORT_A, 0x00); // write 1 to LED port, turning off
+ //}
+
+ }
+}
+
