Diff: main.cpp

Revision:

2:6144709f1700

Parent:

1:5abd129839e7

Child:

3:089a2a754567

diff -r 5abd129839e7 -r 6144709f1700 main.cpp
--- a/main.cpp	Sat Aug 21 07:05:21 2010 +0000
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,88 +0,0 @@
-#include "mbed.h"
-
-/* 
-*  next baby step towards towards a library for MCP23S17
-*  I'm proposing to allow 8-bit and 16-bit conditioning, reads, and writes
-*  and interrupt conditioning
-* 
-*  Unless someone asks for them, I'm not going to implement
-*  multi-reads or writes where a sequence of many bytes are read from or written
-*  to the same register
-* 
-* This is currently experimental code. I'm still checking that I've understood the chip API.
-*/
-
-
-// all register addresses assume IOVCON.BANK = 0 (POR default)
- 
-#define IODIRA 0x00
-#define IODIRB 0x01
-#define IOCON  0x0A
-#define GPIOA  0x12
-#define GPIOB  0x13
-#define OLATA  0x14
-#define OLATB  0x15
-
-// Control settings
-
-#define IOCON_BANK  0x80 // Banked registers
-#define IOCON_BYTE_MODE 0x20 // Disables sequential operation. If bank = 0, operations toggle between A and B registers
-#define IOCON_HAEN  0x08 // Hardware address enable
-
-SPI spi(p5, p6, p7);
-DigitalOut ncs(p20);  // not chip select; bring this low to enable the chip
-char writeOpcode = 0x40; // A0, A1, A2 are tied to ground on the breadboard.
-char readOpcode = writeOpcode | 1; // low order bit = 1 for read
-
-void _write(char address, char data) {
-    ncs = 0;
-    spi.write(writeOpcode);
-    spi.write(address);
-    spi.write(data);
-    ncs = 1;
-}
-
-char _read(char address) {
-    ncs = 0;
-    spi.write(readOpcode); 
-    spi.write(address);
-    char result = spi.write(0);
-    ncs = 1;
-    return result;
-}
-
-void init() {
-    _write(IOCON, (IOCON_BYTE_MODE | IOCON_HAEN )); // Hardware addressing on, operations toggle between A and B registers
-}
-
-void directionA(char direction) {
-     _write(IODIRA, direction); 
-}
-
-void directionB(char direction) {
-     _write(IODIRB, direction); 
-}
-
-void outputA(char byte) {
-    _write(OLATA, byte); 
-}
-
-void outputB(char byte) {
-    _write(OLATB, byte); 
-}
-
-char inputA() {
-    return _read(GPIOA);
-}
-
-int main() {
-    init();
-    directionA(0xFF); // all 8 bits set to input
-    directionB(0x00); // all 8 bits set to ouptut
-    while(1) {
-        wait(0.2);
-        // copy inputs from A to outputs on B
-        outputB(inputA());
-        
-    }
-}