Got disk loading to work.

COPY /b 16bit.boot 16bit.scratch 16bit.loader

qemu-system-x86_64 -fda 16bit.loader

16bit.Output.Tests.s

@@ -0,0 +1,93 @@
+; x86 
+; 16-bit - Real Mode, V86 Mode
+
+; https://codereview.stackexchange.com/questions/230755/display-hexadecimal-value-stored-at-a-register
+
+
+%include "AAL.x86.S"
+%include "AAL.x86.routines.macros.S"
+
+
+; 16-Bit Mode
+[BITS	16]
+; The ORG directive specifies the starting address of a segment
+[ORG	Mem_BootSector_Start]
+
+
+;=============================================================================================================
+; Boot Sector Code
+;=============================================================================================================
+start:
+Video_SetTextMode_80x25
+; Video_SetGraphicsMode_320x200
+; Video_SetGraphicsMode_640x200
+
+;	Exclusive-OR (xor'ing a value to itself zeros the value)
+	xor 	AX, AX
+;	Set Data Segment and Extra Segment to 0x0000
+	mov	DS, AX
+	mov	ES, AX
+;	Set Stack Segment (SS) to to 0x0000
+	mov 	SS, AX
+;	Set Stack Pointer (SP) to the start of the boot sector.
+	mov 	BX, Mem_BootSector_Start
+	mov 	SP, BX
+
+;	String testing
+String_Out	TestStr, [TestStr_len]
+
+	mov	AH, BIOS_Wait
+	mov	CX, 0x02
+int	SystemService
+
+;	Hex Testing
+String_Out	HexTest, [HexTest_len]
+Hex16_ToString	[HexNumA], HexStringA
+Hex16_ToString	[HexNumB], HexStringB
+String_Out	ResultStr, [ResultStr_len]
+String_Out	HexStringA, 4
+String_Out	HexStringB, 4
+
+	mov	AH, BIOS_Wait
+	mov	CX, 0x10
+int	SystemService
+
+Char_Out	char_LF
+Char_Out	char_CR
+
+DumpOut		0x7C00, 512
+
+; Idle
+hang :
+jmp short hang
+
+
+%include "AAL.x86.routines.s"
+
+
+;=============================================================================================================
+; Data
+;=============================================================================================================
+TestStr     : db 	'String Test', char_LF, char_CR
+TestStr_len : dw 	13
+
+HexTest     : db 	'Hex Test', char_LF, char_CR
+HexTest_len : dw 	10
+
+HexNumA     : dw 	0x1994
+HexNumB     : dw 	0x2022
+HexStringA  : db	'0000'
+HexStringB  : db	'0000'
+
+ResultStr     : db	'Result: '
+ResultStr_len : db	8
+
+
+;=============================================================================================================
+; Wrap up
+;=============================================================================================================
+; Byte pad 512 bytes (zeroed)
+times 	510-$+start 	db 0
+; Master Boot Record signature
+db 	0x55
+db 	0xAA