BAT-SD4012_2017
/
ECE4180Lab1_3
I do it
Revision 0:34f3e96385fa, committed 2017-10-05
- Comitter:
- goodguy8791
- Date:
- Thu Oct 05 18:52:46 2017 +0000
- Commit message:
- I do it
Changed in this revision
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/MCP23S17.lib Thu Oct 05 18:52:46 2017 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/romilly/code/MCP23S17/#068b1e8909bb
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/main.cpp Thu Oct 05 18:52:46 2017 +0000 @@ -0,0 +1,83 @@ +//NEED TO ADD “MCP23S17.cpp” AND “MCP23S17.h” TO PROJECT FILE + +// 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 +//DigitalIn pb(p21); +int pb; + +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 + */ + + pb = chip.read(PORT_B) & 0x01; + if(pb == 0){ + chip.write(PORT_A, 1); + }else{ + chip.write(PORT_A, 0); + } + + } +} +
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mbed.bld Thu Oct 05 18:52:46 2017 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/mbed_official/code/mbed/builds/ad3be0349dc5 \ No newline at end of file