support avr architecture based on ATMega32

1. IAR project, see TencentOS-tiny\board\ATMega32\IAR, both 4.12 and 7.20 is supplied.

board/ATMega32/USER/main.c

@@ -0,0 +1,88 @@
+#include "iom32.h"
+#include "uart.h"
+#include "tos_k.h"
+
+#include "stdio.h"
+
+#pragma vector = TIMER1_OVF_vect
+__interrupt void TIMER1_OVF(void)
+{
+    if (tos_knl_is_running()) {
+        tos_knl_irq_enter();
+        tos_tick_handler();
+        tos_knl_irq_leave();
+    }
+}
+
+#pragma vector = USART_RXC_vect
+__interrupt void UART0_rx(void)
+{
+    unsigned char rx_data;
+    rx_data = UDR;
+}
+
+void interrupt_enable(void)
+{
+    SREG |= (1 << 7);
+}
+
+void task1_entry(void *arg)
+{
+    while (1) {
+        uart_send_string("task1\r\n");
+        tos_task_delay(2000);
+    }
+}
+
+void task2_entry(void *arg)
+{
+    while (1) {
+        uart_send_string("task2\r\n");
+        tos_task_delay(3000);
+    }
+}
+
+k_task_t task1;
+k_stack_t task1_stack[128];
+
+k_task_t task2;
+k_stack_t task2_stack[128];
+
+#define APPLICATION_TASK_STK_SIZE       256
+
+k_task_t task_app;
+k_stack_t task_app_stack[128];
+
+void application_entry(void * arg)
+{
+    tos_task_create(&task1, "task1", task1_entry, NULL,
+                        4,
+                        task1_stack, sizeof(task1_stack),
+                        0);
+
+    tos_task_create(&task2, "task2", task2_entry, NULL,
+                        4,
+                        task2_stack, sizeof(task2_stack),
+                        0);
+}
+
+int main(void)
+{
+    uart_init(9600);
+    timer1();
+
+    uart_send_string("welcome to TencentOS tiny!\r\n");
+    printf("welcome to TencentOS tiny!\r\n");
+
+    tos_knl_init();
+
+    tos_task_create(&task_app, "app", application_entry, NULL,
+                        4,
+                        task_app_stack, sizeof(task_app_stack),
+                        0);
+
+    tos_knl_start();
+
+    while (1);
+}
+