8051 – TRAINER BOARD

PS-TRAINER-8051 trainer kit is proposed to smooth the progress of learning and developing designs of MCU from Intel and NXP. It has facility to connect PC’s 101/104 Keyboard, to enter user programs in Assembly languages. Serial communication achieved using 8051. It also supports C & assembly language in standalone kit (P89V51RD2). It’s designed as to facilitate On-board Programmer for NXP 8051 MCU through ISP on serial port.

LED (LIGHT EMITTING DIODE)

Light Emitting Diodes (LED) is the most commonly used components, usually for displaying pins digital states. Typical uses of LEDs include alarm devices, timers and confirmation of user input such as a mouse click or keystroke.

INTERFACING LED

Fig. 1 shows how to interface the LED to microcontroller. As you can see the Anode is connected through a resistor to GND & the Cathode is connected to the Microcontroller pin. So when the Port Pin is HIGH the LED is OFF & when the Port Pin is LOW the LED is turned ON.

INTERFACING LED WITH 8051

LED in 8051 Trainer Board works by turning ON a LED & then turning it OFF & then looping back to START. However the operating speed of microcontroller is very high so the flashing frequency will also be very fast to be detected by human eye.

PIN ASSIGNMENT WITH 8051

CIRCUIT DIAGRAM TO INTERFACE LED WITH 8051

ASSEMBLY PROGRAM TO ON AND OFF LED USING 8051

MEMORY ADDRESS	OPCODE	MNEMONICS
9100	74 55	L1:MOV A,#FF
9102	7C	MOV B0,A
9104	12 91 0F	LCALL DELAY
9107	74 00	MOV A,#00
9109	7C	MOV B0,A
910b	12 91 0F	LCALL DELAY
910D	80 F9	SJMP L1
910F	7D 05	DELAY: MOV R5,#05
9111	7C FF	H3       MOV R4,#FF
9113	7B FF	H2       MOV R3,#FF
9115	DB FE	H1:     DJNZ R3,H1
9117	DC FA	DJNZ R4,H2
9119	DD F6	DJNZ R5,H3
911B	22	RET