So far, I have examined Interrupt controller register and designed "Interrupt.c" performing to enable, disable Interrupt, and define handlers.
Eventhough I made Interrupt method, I can't utilize Interrupt without any hardware.
In CH6-3, I will set UART interrupt and define UART interrupt handlers.
Uart.c
void Hal_uart_init(void){
Uart->uartcr.bits.UARTEN=0;
Uart->uartcr.bits.TXE=1;
Uart->uartcr.bits.RXE=1;
Uart->uartcr.bits.UARTEN=1;
Uart->uartimsc.bits.RXIM = 1;
// enable input interrupt
Hal_interrupt_enable(UART_INTERRUPT0);
Hal_interrupt_register_handler(interrupt_handler, UART_INTERRUPT0);
}
static void interrupt_handler(void){
uint8_t ch = Hal_uart_get_char();
Hal_uart_put_char(ch);
}
- I add 3 lines below to "Uart.c".
- "Hal_interrupt_enable(UART_INTERRUPT0)" enables Uart interrupt. (defined in Interrupt.c)
- "Hal_interrupt_register_handler(interrupt_handler, UART_INTERRUPT0)" regist a handler for Uart interrupt.
익셉션
- When an IRQ interrupt invoked, the cpu changes its mode to the irq mode.
- The first instruction after the change is the execption handler defined in "Entry.S".
- I had set nothing to the IRQ execption handler.
#include "ARMv7AR.h"
#include "MemoryMap.h"
.text
.code 32
.global vector_start
.global vector_end
vector_start:
LDR PC, reset_handler_addr
LDR PC, undef_handler_addr
LDR PC, svc_handler_addr
LDR PC, pftch_abt_handler_addr
LDR PC, data_abt_handler_addr
B .
LDR PC, irq_handler_addr
LDR PC, fiq_handler_addr
reset_handler_addr: .word reset_handler
undef_handler_addr: .word dummy_handler
svc_handler_addr: .word dummy_handler
pftch_abt_handler_addr: .word dummy_handler
data_abt_handler_addr: .word dummy_handler
// 여기를 바꿨다.
irq_handler_addr: .word Irq_Handler
fiq_handler_addr: .word Fiq_Handler- dummy_handler로 아무 일도 안했던 것을 "Irq_Handler"로 바꿧다.
- Then I have to define what Irq_Handler do.
#include "stdbool.h"
#include "stdint.h"
#include "HalInterrupt.h"
__attribute__ ((interrupt("IRQ"))) void Irq_Handler(void){
Hal_interrupt_run_handler();
}- It is a definition of the "Irq_Handler"
- Hal_interrupt_run_handler is defined in "Interrupt.c"
- It executes the handler routine mapped to the given interrupt number.
I' done now...
Keyboard input and display works well.
gg