09-11-2012, 03:31 PM
Seven Segment Display Interfacing With 8051
7SEGment.pptx (Size: 201.74 KB / Downloads: 25)
Seven Segment Display
Output Device
Common Cathode Seven Segment Display
Common Anode Seven Segment Display
LED displays are
– power-hungry (10ma per LED)
– Pin-hungry (8 pins per 7-seg display)
Limitation: only digits and few characters can be displayed
To view display from far distance
Interfacing Multiple Seven segment LED
Direct Interfacing
- one LED requires one PORT
-Not feasible because only 4 ports in 8051
-All ports are engaged in display
-More LEDs can not be connected
Software simplicity
Multiple LED Interfacing Using Latch with Each LED
Using Latch with
Each LED
Hardware cost
Increases-4 latch
No. of pins
- 8+No.of LED
No Refreshing burden
on software