diff --git a/ES/Lab/LAB4/ASCIItoHEX.asm b/ES/Lab/LAB4/ASCIItoHEX.asm
new file mode 100644
index 0000000..58e4c88
--- /dev/null
+++ b/ES/Lab/LAB4/ASCIItoHEX.asm
@@ -0,0 +1,38 @@
+	AREA RESET, DATA, READONLY
+	EXPORT __Vectors
+__Vectors
+	DCD 0x10001000
+	DCD Reset_Handler
+	ALIGN
+	
+	AREA MYCODE, CODE, READONLY
+	ENTRY
+	EXPORT Reset_Handler
+
+Reset_Handler
+	LDR R0, =SRC
+	LDR R3, =DST
+    MOV R1, #0
+	MOV R10, #8
+	
+UP
+    LDRB R2, [R0], #1
+    CMP R1, #'9'
+    BCC DOWN
+    SUB R2, #7
+	
+DOWN
+	SUB R2, #0x30
+    LSL R1, #4
+    ORR R1, R1, R2
+    SUBS R10, #1
+	BNE UP
+
+    STR R1, [R3]
+SRC DCB "12AB34CF"
+	
+	AREA mydata, DATA, READWRITE
+
+DST DCD 0
+
+	END
\ No newline at end of file