Исходник на C++
template <class THardwareIo> class T16750 : public TUART16x50
{
    [...]
    __noinline void Halt(int MaxWait_mks = 1000 * 1000) const
    {
        while((ReadLineStatus() & (LSR_TSRE | LSR_THRE)) != (LSR_TSRE | LSR_THRE) && MaxWait_mks > 0)
        {
            KeStallExecutionProcessor(25);
            MaxWait_mks -= 25;
        }

        for(int MaxRead = 1024; (ReadLineStatus() & LSR_DR) && MaxRead > 0; MaxRead--)
            ReadReceiveBuffer();

        ReadLineStatus();
        ReadModemStatus()
        ReadInterruptIdentRaw();
    }
    [...]

Код для Memory Mapped I/O
; _this$ = esi

$L17612:
	mov	eax, [esi]
	add	eax, 5
	mov	al, [eax]
	and	al, 96
	cmp	al, 96
	je	$L17613

	cmp	_MaxWait_mks$[esp-4], 0
	jle	$L17613

	push	25
	call	__imp__KeStallExecutionProcessor@4
	sub	_MaxWait_mks$[esp-4], 25
	jmp	$L17612
$L17613:
	mov	eax, [esi]
	mov	ecx, 1024
$L17615:
	test	BYTE PTR [eax+5], 1
	je	$L17617

	test	ecx, ecx
	jle	$L17617

	mov	dl, [eax]
	dec	ecx
	jmp	$L17615
$L17617:
	mov	cl, [eax+5]
	mov	cl, [eax+6]
	mov	al, [eax+2]
	ret	4

Код для Port I/O
; _this$ = eax

	push	esi
	push	edi
	mov	esi, eax
$L17408:
	mov	edx, [esi]
	add	edx, 5
	in	al, dx
	and	al, 96
	cmp	al, 96
	je	$L17409

	cmp	_MaxWait_mks$[esp+4], 0
	jle	$L17409

	push	25
	call	__imp__KeStallExecutionProcessor@4
	sub	_MaxWait_mks$[esp+4], 25
	jmp	$L17408
$L17409:
	mov	ecx, [esi]
	mov	edi, 1024
	lea	esi, [ecx+5]
$L17411:
	mov	dx, si
	in	al, dx
	test	al, 1
	je	$L17413

	test	edi, edi
	jle	$L17413

	mov	dx, cx
	in	al, dx
	dec	edi
	jmp	$L17411
$L17413:
	lea	edx, [ecx+5]
	in	al, dx
	lea	edx, [ecx+6]
	in	al, dx
	lea	edx, [ecx+2]
	pop	edi
	in	al, dx
	pop	esi
	ret	4