Diff: main.cpp

Revision:

4:15297eea34f6

Parent:

3:8f437a811ecf

--- a/main.cpp	Mon Aug 23 10:59:22 2010 +0000
+++ b/main.cpp	Sat Aug 28 09:51:44 2010 +0000
@@ -4,10 +4,10 @@
 *
 * See http://mbed.org/users/romilly/notebook/mcp23s17-addressable-16-bit-io-expander-with-spi/
 *
-* NB this code is inteded to test the driver library, not the chip
+* NB this code is intended to test the driver library, not the chip
 * which is assumed to work as specified
 * MCP23S17 datasheet http://ww1.microchip.com/downloads/en/DeviceDoc/21952b.pdf
-* version 0.3
+* version 0.4
 */
 
 #include "mbed.h"
@@ -22,12 +22,17 @@
 MCP23S17 chip = MCP23S17(spi, p20, writeOpcode); // create MCP23S17
 DigitalOut    chipNotReset(p14); // connected to ~reset of the MCP23S17
 DigitalInOut chipA0(p12);  // connected to Port A bit 0 of the MCP23S17
+DigitalInOut chipA1(p30);     // connected to Port A bit 1 via 100k resistor
 DigitalInOut  chipB0(p10); // connected to Port B bit 0 of the MCP23S17
 DigitalIn   chipIntA(p16); // connected to INTA on the MCP23S17
 DigitalIn   chipIntB(p18); // connected to INTB on the MCP23S17
 
 void reset() {
     // I'm not sure we need the delays, but better safe than sorry.
+    // Ensure mbed bi-directional pins set to input
+    chipA0.input();
+    chipA1.input();
+    chipB0.input();
     chipNotReset = 0;  // reset chip
     wait_us(10);
     chipNotReset = 1;
@@ -103,7 +108,7 @@
     chip.direction(PORT_B, 0x01); //  bit 0 set to input
     chipB0 = 1;
     chip.interruptEnable(PORT_B, 0x01); // interupt enabled on pin 0
-    wait_us(1); 
+    wait_us(1);
     checkEqual(0, int(chipIntB), "interruptB");
 }
 
@@ -113,14 +118,14 @@
     chip.direction(PORT_B, 0x01); //  bit 0 set to input
     chipB0 = 1;
     chip.interruptEnable(PORT_B, 0x01); // interupt enabled on pin 0
-    wait_us(1); 
+    wait_us(1);
     checkEqual(0, int(chipIntB), "interruptB");
     checkEqual(1, int(chipIntA), "before mirroring"); // no interrupt A yet
     chip.mirrorInterrupts(true);
-    wait_us(1); 
+    wait_us(1);
     checkEqual(0, int(chipIntA), "after mirroring");
     chip.mirrorInterrupts(false);
-    wait_us(1); 
+    wait_us(1);
     checkEqual(1, int(chipIntA), "after mirroring turned off");
 }
 
@@ -138,17 +143,25 @@
 }
 
 void testInterruptControlAndDefaultValueOnPortA() {
-     reset();
-     chipA0.output(); // output from the mbed
-     chip.direction(PORT_A, 0x01); //  bit 0 set to input
-     chipA0 = 0;
-     checkEqual(1, int(chipIntA),"interrupt ACTIVE_LOW by default");
-     chip.interruptEnable(PORT_A, 0x01); // interupt enabled on pin 0
-     chip.defaultValue(PORT_A, 0x01); // default value != input value
-     checkEqual(1, int(chipIntA),"still no interrupt"); // interrupt control still set to interrupt on change
-     chip.interruptControl(PORT_A, 0x01);
-     wait_us(1);
-     checkEqual(0, int(chipIntA), "expecting interrupt as default != input");
+    reset();
+    chipA0.output(); // output from the mbed
+    chip.direction(PORT_A, 0x01); //  bit 0 set to input
+    chipA0 = 0;
+    checkEqual(1, int(chipIntA),"interrupt ACTIVE_LOW by default");
+    chip.interruptEnable(PORT_A, 0x01); // interupt enabled on pin 0
+    chip.defaultValue(PORT_A, 0x01); // default value != input value
+    checkEqual(1, int(chipIntA),"still no interrupt"); // interrupt control still set to interrupt on change
+    chip.interruptControl(PORT_A, 0x01);
+    wait_us(1);
+    checkEqual(0, int(chipIntA), "expecting interrupt as default != input");
+}
+
+void testConfigurePullUpsOnPortA() {
+    reset();
+    chipA1.output();
+    checkEqual(0, chip.read(PORT_A), "without pull-up input should be 0");
+    chip.configurePullUps(PORT_A, 0x02); // pin A1 pull-up enabled
+    checkEqual(2, chip.read(PORT_A), "pull-up should raise chip input to 1");
 }
 
 int main() {
@@ -161,6 +174,7 @@
     testInterruptPolarity();
     testMirrorInterrupts();
     testInterruptControlAndDefaultValueOnPortA();
+    testConfigurePullUpsOnPortA();
     // testInterruptControlAndDefaultValueOnPortB();
     // testInterruptCaptureA();
     // testInterruptCaptureB();