ECE 4180 Lab 1 Extra Credit 4
Fork of MCP23S17_Basic_IO_Demo by
Revision 3:52b465070371, committed 2018-10-09
- Comitter:
- abraha2d
- Date:
- Tue Oct 09 00:16:03 2018 +0000
- Parent:
- 2:934a0500abde
- Commit message:
- Save point
Changed in this revision
| main.cpp | Show annotated file Show diff for this revision Revisions of this file |
| mbed.bld | Show annotated file Show diff for this revision Revisions of this file |
--- a/main.cpp Fri Jan 28 02:04:05 2011 +0000
+++ b/main.cpp Tue Oct 09 00:16:03 2018 +0000
@@ -13,26 +13,29 @@
#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
+// mbed p19 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;
+char Opcode2 = 0x42;
// Next create a MCP23S17
-// mbed p20 is connected to ~chipSelect on the MCP23S17
-MCP23S17 chip = MCP23S17(spi, p20, Opcode);
+// mbed p19 is connected to ~chipSelect on the MCP23S17
+MCP23S17 chip = MCP23S17(spi, p19, Opcode);
+MCP23S17 chip2 = MCP23S17(spi, p19, Opcode2);
// 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() {
+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.
@@ -45,22 +48,13 @@
//
// Set all 8 Port A bits to output direction
chip.direction(PORT_A, 0x00);
+ chip2.direction(PORT_A, 0x00);
// Set all 8 Port B bits to input direction
chip.direction(PORT_B, 0xFF);
+ chip2.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
+ chip2.write(PORT_A, !chip.read(PORT_B) & 0x01);
}
}
--- a/mbed.bld Fri Jan 28 02:04:05 2011 +0000 +++ b/mbed.bld Tue Oct 09 00:16:03 2018 +0000 @@ -1,1 +1,1 @@ -http://mbed.org/users/mbed_official/code/mbed/builds/9114680c05da +https://os.mbed.com/users/mbed_official/code/mbed/builds/e95d10626187 \ No newline at end of file
