lhiggs CSUM
/
UM6_IMU_AHRS_2012
Communication program for the chrobotics UM6 9-DOF IMU AHRS.
Diff: MODSERIAL/example2.cpp
- Revision:
- 0:03c649c76388
diff -r 000000000000 -r 03c649c76388 MODSERIAL/example2.cpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/MODSERIAL/example2.cpp Fri Sep 28 00:40:29 2012 +0000 @@ -0,0 +1,167 @@ +/* + Copyright (c) 2011 Andy Kirkham + + Permission is hereby granted, free of charge, to any person obtaining a copy + of this software and associated documentation files (the "Software"), to deal + in the Software without restriction, including without limitation the rights + to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + copies of the Software, and to permit persons to whom the Software is + furnished to do so, subject to the following conditions: + + The above copyright notice and this permission notice shall be included in + all copies or substantial portions of the Software. + + THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + THE SOFTWARE. + + @file example2.cpp + @purpose Demos a simple messaging system. + @version see ChangeLog.c + @date Jan 2011 + @author Andy Kirkham +*/ + +/* + This example demostrates a simple "messaging" system. You can use it with + a terminal program to test it out or write a cusom C#/C++/VB/etc program + to read and write messages to or from the Mbed. The default baud rate in + this example is 115200. + + In this example, the LEDs are controlled and pins p21 to p24 are set as + InterruptIn and send messages out when their value changes. + + To use, hook up the MBed USB and open your fav terminal. All messages + end with the \n character, don't forget to hit carriage return!. + As an example:- + + to switch on LED1 send LED1:1\n, off is LED1:0\n and toggle is LED1:2\n + to switch on LED2 send LED2:1\n, off is LED2:0\n and toggle is LED2:2\n + to switch on LED3 send LED3:1\n, off is LED3:0\n and toggle is LED3:2\n + to switch on LED4 send LED4:1\n, off is LED4:0\n and toggle is LED4:2\n + + When a pin change on p21 to p24 happens, a message is sent. As an example + when p21 goes low PIN21:0\n is sent, when goes high PIN21:1\n is sent. + + Note, the InterruptIn pins p21 to p24 are setup to have pullups. This means + they are high. To activate them use a wire to short the pin to 0volts. + + If you find that p21 to p24 sent a lot of on/off/on/off then it's probably + due to "bounce". If you are connecting a mechanical switch to a pin you + may prefer to use the PinDetect library rather than using InterruptIn. + @see http://mbed.org/users/AjK/libraries/PinDetect/latest + + One point you may notice. Incoming messages are processed via main()'s + while(1) loop whereas pin changes have their messages directly sent. + The reason for this is when MODSERIAL makes callbacks to your application + it is in "interrupt context". And one thing you want to avoid is spending + lots of CPU time in that context. So, the callback moves the message from + the input buffer to a local holding buffer and it then sets a bool flag + which tells main()'s while(1) loop to process that buffer. This means the + time spent doing the real incoming message handing is within your program + and not within MODSERIAL's interrupt context. So you may ask, why not do + the same for out going messages? Well, because MODSERIAL output buffers + all your sent content then sending chars is very fast. MODSERIAL handles + all the nitty gritty bits for you. You can just send. This example uses + puts() to send the message. If you can, always try and use sprintf()+puts() + rathe than printf(), printf() is known to often screw things up when used + within an interrupt context. Better still, just use puts() and do away + with any of the crappy ?printf() calls if possible. But I found the code + below to work fine even at 115200baud. + +*/ + + +#ifdef COMPILE_EXAMPLE1_CODE_MODSERIAL + +#include "mbed.h" +#include "MODSERIAL.h" + +#define MESSAGE_BUFFER_SIZE 32 + +DigitalOut led1(LED1); +DigitalOut led2(LED2); +DigitalOut led3(LED3); +DigitalOut led4(LED4); + +InterruptIn P21(p21); +InterruptIn P22(p22); +InterruptIn P23(p23); +InterruptIn P24(p24); + +MODSERIAL messageSystem(USBTX, USBRX); + +char messageBufferIncoming[MESSAGE_BUFFER_SIZE]; +char messageBufferOutgoing[MESSAGE_BUFFER_SIZE]; +bool messageReceived; + +void messageReceive(MODSERIAL_IRQ_INFO *q) { + MODSERIAL *sys = q->serial; + sys->move(messageBufferIncoming, MESSAGE_BUFFER_SIZE); + messageReceived = true; + return 0; +} + +void messageProcess(void) { + if (!strncmp(messageBufferIncoming, "LED1:1", sizeof("LED1:1")-1)) led1 = 1; + else if (!strncmp(messageBufferIncoming, "LED1:0", sizeof("LED1:0")-1)) led1 = 0; + else if (!strncmp(messageBufferIncoming, "LED1:2", sizeof("LED1:2")-1)) led1 = !led1; + + else if (!strncmp(messageBufferIncoming, "LED2:1", sizeof("LED2:1")-1)) led2 = 1; + else if (!strncmp(messageBufferIncoming, "LED2:0", sizeof("LED2:0")-1)) led2 = 0; + else if (!strncmp(messageBufferIncoming, "LED2:2", sizeof("LED2:2")-1)) led2 = !led2; + + else if (!strncmp(messageBufferIncoming, "LED3:1", sizeof("LED3:1")-1)) led3 = 1; + else if (!strncmp(messageBufferIncoming, "LED3:0", sizeof("LED3:0")-1)) led3 = 0; + else if (!strncmp(messageBufferIncoming, "LED3:2", sizeof("LED3:2")-1)) led3 = !led3; + + else if (!strncmp(messageBufferIncoming, "LED4:1", sizeof("LED4:1")-1)) led4 = 1; + else if (!strncmp(messageBufferIncoming, "LED4:0", sizeof("LED4:0")-1)) led4 = 0; + else if (!strncmp(messageBufferIncoming, "LED4:2", sizeof("LED4:2")-1)) led4 = !led4; + + messageReceived = false; +} + +#define PIN_MESSAGE_SEND(x,y) \ + sprintf(messageBufferOutgoing,"PIN%02d:%d\n",x,y);\ + messageSystem.puts(messageBufferOutgoing); + +void pin21Rise(void) { PIN_MESSAGE_SEND(21, 1); } +void pin21Fall(void) { PIN_MESSAGE_SEND(21, 0); } +void pin22Rise(void) { PIN_MESSAGE_SEND(22, 1); } +void pin22Fall(void) { PIN_MESSAGE_SEND(22, 0); } +void pin23Rise(void) { PIN_MESSAGE_SEND(23, 1); } +void pin23Fall(void) { PIN_MESSAGE_SEND(23, 0); } +void pin24Rise(void) { PIN_MESSAGE_SEND(24, 1); } +void pin24Fall(void) { PIN_MESSAGE_SEND(24, 0); } + +int main() { + + messageReceived = false; + messageSystem.baud(115200); + messageSystem.attach(&messageReceive, MODSERIAL::RxAutoDetect); + messageSystem.autoDetectChar('\n'); + + // Enable pullup resistors on pins. + P21.mode(PullUp); P22.mode(PullUp); P23.mode(PullUp); P24.mode(PullUp); + + // Fix Mbed library bug, see http://mbed.org/forum/bugs-suggestions/topic/1498 + LPC_GPIOINT->IO2IntClr = (1UL << 5) | (1UL << 4) | (1UL << 3) | (1UL << 2); + + // Attach InterruptIn pin callbacks. + P21.rise(&pin21Rise); P21.fall(&pin21Fall); + P22.rise(&pin22Rise); P22.fall(&pin22Fall); + P23.rise(&pin23Rise); P23.fall(&pin23Fall); + P24.rise(&pin24Rise); P24.fall(&pin24Fall); + + while(1) { + // Process incoming messages. + if (messageReceived) messageProcess(); + } +} + +#endif