Rodrigo Almeida
Pão de Queijo Development Board. This repo has all libraries from pqdb shield.
Pão de Queijo development board is a shield for add-on on any arduino compatible board.
This project presents the libraries to control the board peripherals using mbed framework. The libraries works as interfaces to keep the main code compatible with the examples from the book "Programação de sistemas embarcados". The peripherals on the board are presented on the folowing picture
The main objective of the project is to develop a low cost, easy to assemble board with a group of peripheral that allows one to start learning embedded systems. The board was routed on one side copper PCB to make easier to buid it yourself.
The source code for Arduino boards (wiring) can be found on: https://github.com/projetopqdb/PQDB-Arduino
The source code for freedom frdm KL05 board (using direct register access) can be found on: https://github.com/projetopqdb/PQDB-KL05Z
The source code from the board schematics and layout can be found on: https://github.com/projetopqdb/PQDB-Hardware
Diff: kernel.cpp
- Revision:
- 4:357a34c10ef2
diff -r 6ca4d7dd8bea -r 357a34c10ef2 kernel.cpp
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/kernel.cpp Tue Oct 03 00:17:53 2017 +0000
@@ -0,0 +1,86 @@
+#include "kernel.h"
+#include "mbed.h"
+#include "lcd.h"
+
+
+#define MIN_INT -30000
+Ticker tick;
+
+static process* pool[POOL_SIZE];
+//primeiro elemento do buffer
+int start;
+//�ltimo elemento do buffer
+int end;
+
+//adiciona os processos no pool
+char kernelAddProc(process* func){
+ // adiciona processo somente se houver espa�o livre
+ //o fim nunca pode coincidir com o inicio
+ if ( ((end+1)%POOL_SIZE) != start){
+ //adiciona o novo processo e agenda para executar imediatamente
+ func->deadline += func->period;
+ pool[end] = func;
+ end = (end+1)%POOL_SIZE;
+ return SUCCESS; //sucesso
+ }
+ return FAIL; //falha
+}
+//inicializa o kernel em conjunto com a controladora de drivers
+void kernelInit(void){
+ start = 0;
+ end = 0;
+ tick.attach(&kernelTick, 0.01); // setup ticker to call flip every 0.7 seconds
+}
+//executa os processos do 'pool' de acordo com seus tempos de execu��o
+void kernelLoop(void){
+ unsigned int count;
+ unsigned int next;
+ process* tempProc;
+ for(;;){
+ if (start != end){
+ //Procura a pr�xima fun��o a ser executada com base no tempo
+ count = (start+1)%POOL_SIZE;
+ next = start;
+ while(count!=end){
+ if ((pool[count]->deadline) < (pool[next]->deadline)){
+ next = count;
+ }
+ //para poder incrementar e ciclar o contador
+ count = (count+1)%POOL_SIZE;
+ }
+ //troca e coloca o processo com menor tempo como o pr�ximo
+ tempProc = pool[next];
+ pool[next] = pool[start];
+ pool[start] = tempProc;
+ while((pool[start]->deadline) > 0){
+ //lcdCommand(0xC0);
+ //lcdNumber(pool[start]->deadline);
+ //coloca a cpu em modo de economia de energia
+ }
+ //retorna se precisa repetir novamente ou n�o
+ switch (pool[start]->function()) {
+ case REPEAT:
+ kernelAddProc(pool[start]);
+ break;
+ case FAIL:
+ break;
+ default: ;
+ }
+ //pr�xima fun��o
+ start = (start + 1) % POOL_SIZE;
+ }
+ }
+}
+//atualiza os tempos de execu��o dos processos
+void kernelTick(void){
+ int proc;
+ proc = start;
+ while(proc!=end){
+ if((pool[proc]->deadline)>(MIN_INT)){
+ pool[proc]->deadline--;
+ }
+
+ proc = (proc+1)%POOL_SIZE;
+ }
+
+}