Unitech MR350MKII manual RS-485 port serial I/O using

03	Enable RS-232 port			3-27
04	Disable RS-232 port			3-27
00	Set Communication parameters			3-27
05	Set RTS signal of RS-232 port			3-29
06	Read CTS signal of RS-232 port			3-29
RS-485 port serial I/O using			INT 33H	3-29
01	Input data			3-29
02	Output data			3-30
03	Enable RS-485 port for serial I/O			3-30
04	Disable RS-485 port for serial I/O			3-30
00	Set Communication parameters			3-31
05	Open RS-485 multi-bus to send out data			3-32
06	Close RS-485 multi-bus (release RS-485 bus)			3-33
3.5.	Relay Output / Digit Input / Buzzer / LED Indicator			3-34
Set LED indicator ON/OFF		INT 09H		3-34
Read Photo Coupler Level state			INT 08H	3-34
Activate/Deactivate Relay ports			INT 09H	3-35
1A	Buzzer On/Off INT 21H			3-35
1A	Set buzzer volume INT 21H			3-36
1B	Get Security state	INT 21H		3-36
1B	Alarm On/Off INT 21H			3-36
54	Buzzer volume control with user-defined frequency and time INT 21H			3-37
Buzzer volume control with predefined frequency and time INT 35H				3-37
3.6.	Internal/ External reader Port: INT 21H			3-38
51	Enable/Disable External reader port			3-38
18	Set external slot reader (only available for Barcode and Magnetic reader)			3-38
50	Read data from external reader(only available for Barcode and Magnetic reader)			3-39
52	Read Internal port			3-39
53	Enable/disable Internal reader			3-40
1F	Enable/Disable the Decoder of Wiegand Format (Proximity reader)			3-40
1F	Get Decoder status of Wiegand Format (Proximity reader)			3-41
1A	Assign barcode or magnetic stripe input of Internal reader			3-41
1F	Enable the decoding of a barcode symbology			3-42
3.7.	Miscellaneous: INT 21H			3-42
1A	Check lithium battery level			3-42
1B	Get Address ID of the terminal			3-43
25	Set interrupt vector			3-43
35	Get interrupt vector			3-43
36	Get free disk cluster			3-44
1A	Enable/disable system key-pressing commands: Warm start, Invoke user command menu,
Invoke supervisor mode				3-44
1E	Change the Keyboard map			3-44
3.8.	DOS Manager			3-46
01	Read stdin (wait if no key) and write it to stdout			3-46
02	Write stdout			3-46
03	Read stdaux (COM2 RS-232 port)			3-47
04	Write stdaux (COM2 RS-232 port)			3-47
06	Read / Write stdin or return 0 if none is ready			3-47
07	Read stdin (wait if no key)			3-48
08	Read stdin (wait if no key)			3-48
09	Write character string to stdout			3-48
0A	Keyboard buffer input			3-49
0B	Keyhit check			3-49
2A	Get System date			3-49
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