コード例 #1
0
ファイル: screen.c プロジェクト: Danielhu229/geekos-task
/*
 * Update the location of the hardware cursor.
 */
static void Update_Cursor(void) {
    /*
     * The cursor location is a character offset from the beginning
     * of page memory (I think).
     */
    uint_t characterPos = (s_cons.row * NUMCOLS) + s_cons.col;
    uchar_t origAddr;

    /*
     * Save original contents of CRT address register.
     * It is considered good programming practice to restore
     * it to its original value after modifying it.
     */
    origAddr = In_Byte(CRT_ADDR_REG);
    IO_Delay();

    /* Set the high cursor location byte */
    Out_Byte(CRT_ADDR_REG, CRT_CURSOR_LOC_HIGH_REG);
    IO_Delay();
    Out_Byte(CRT_DATA_REG, (characterPos >> 8) & 0xff);
    IO_Delay();

    /* Set the low cursor location byte */
    Out_Byte(CRT_ADDR_REG, CRT_CURSOR_LOC_LOW_REG);
    IO_Delay();
    Out_Byte(CRT_DATA_REG, characterPos & 0xff);
    IO_Delay();

    /* Restore contents of the CRT address register */
    Out_Byte(CRT_ADDR_REG, origAddr);
}
コード例 #2
0
ファイル: ne2000.c プロジェクト: Foshie/Classes
void NE2000_Handle_Ring_Buffer_Overflow(struct Net_Device *device) {
    int txp, resend;
    ulong_t baseAddr = device->baseAddr;
    /* 1. Read and store the value of the TXP bit */
    txp = In_Byte(baseAddr + NE2K_CR) & NE2K_CR_TXP;

    /* 2. Issue the STOP command to the NIC */
    Out_Byte(baseAddr + NE2K_CR, 0x21);

    /* 3. Wait for at least 1.6 ms */
    IO_Delay();

    /* 4. Clear the NIC’s Remote Byte Count */
    Out_Byte(baseAddr + NE2K0W_RBCR0, 0x00);
    Out_Byte(baseAddr + NE2K0W_RBCR1, 0x00);

    /* 5. Handle resend */
    if (!txp) {
        resend = 0;
    } else {
        int isr = In_Byte(baseAddr + NE2K0R_ISR);
        if ((isr & NE2K_ISR_PTX) || (isr & NE2K_ISR_TXE)) {
            resend = 0;
        } else {
            resend = 1;
        }
    }

    /* 6. Place the NIC into loopback mode */
    Out_Byte(baseAddr + NE2K0W_TCR, 0x02);

    /* 7. Issue START command to the NIC */
    Out_Byte(baseAddr + NE2K_CR, 0x22);

    /* 8. Remove one or more packets from the receive buffer ring */
    NE2000_Do_Receive(device);

    /* 9. Reset the overwrite warning (OVW) bit in the ISR */
    Out_Byte(baseAddr + NE2K0R_ISR, NE2K_ISR_OVW);

    /* 10. Take the NIC out of loopback */
    Out_Byte(baseAddr + NE2K0W_TCR, 0x00);

    /* 11. Restart the interrupted transmit if resend = 1 */
    if (resend) {
        Out_Byte(baseAddr + NE2K_CR, 0x26);
    }
}
コード例 #3
0
ファイル: keyboard.c プロジェクト: epowers/palacios
/*
 * Handler for keyboard interrupts.
 */
static void Keyboard_Interrupt_Handler(struct Interrupt_State* state)
{
    uchar_t status, scanCode;
    unsigned flag = 0;
    bool release = false, shift;
    Keycode keycode;

    Begin_IRQ(state);

    status = In_Byte(KB_CMD);
    IO_Delay();

    if ((status & KB_OUTPUT_FULL) != 0) {
	/* There is a byte available */
	scanCode = In_Byte(KB_DATA);
	IO_Delay();
/*
 *	Print("code=%x%s\n", scanCode, (scanCode&0x80) ? " [release]" : "");
 */

	if (scanCode & KB_KEY_RELEASE) {
	    release = true;
	    scanCode &= ~(KB_KEY_RELEASE);
	}

	if (scanCode >= SCAN_TABLE_SIZE) {
	    Print("Unknown scan code: %x\n", scanCode);
	    goto done;
	}

	/* Process the key */
	shift = ((s_shiftState & SHIFT_MASK) != 0);
	keycode = shift ? s_scanTableWithShift[scanCode] : s_scanTableNoShift[scanCode];

	/* Update shift, control and alt state */
	switch (keycode) {
	case KEY_LSHIFT:
	    flag = LEFT_SHIFT;
	    break;
	case KEY_RSHIFT:
	    flag = RIGHT_SHIFT;
	    break;
	case KEY_LCTRL:
	    flag = LEFT_CTRL;
	    break;
	case KEY_RCTRL:
	    flag = RIGHT_CTRL;
	    break;
	case KEY_LALT:
	    flag = LEFT_ALT;
	    break;
	case KEY_RALT:
	    flag = RIGHT_ALT;
	    break;
	default:
	    goto noflagchange;
	}

	if (release)
	    s_shiftState &= ~(flag);
	else
	    s_shiftState |= flag;
			
	/*
	 * Shift, control and alt keys don't have to be
	 * queued, flags will be set!
	 */
	goto done;

noflagchange:
	/* Format the new keycode */
	if (shift)
	    keycode |= KEY_SHIFT_FLAG;
	if ((s_shiftState & CTRL_MASK) != 0)
	    keycode |= KEY_CTRL_FLAG;
	if ((s_shiftState & ALT_MASK) != 0)
	    keycode |= KEY_ALT_FLAG;
	if (release)
	    keycode |= KEY_RELEASE_FLAG;
		
	/* Put the keycode in the buffer */
	Enqueue_Keycode(keycode);

	/* Wake up event consumers */
	Wake_Up(&s_waitQueue);

	/*
	 * Pick a new thread upon return from interrupt
	 * (hopefully the one waiting for the keyboard event)
	 */
	g_needReschedule = true;
    }

done:
    End_IRQ(state);
}