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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 |
diff -r 934a0500abde -r 52b465070371 main.cpp --- 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); } }
diff -r 934a0500abde -r 52b465070371 mbed.bld --- 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