28122 Parallax Inc, 28122 Datasheet - Page 174

• Manufacturer Part Number: 28122
• Description: KIT WHAT'S A MICRO:PARTS ONLY
• Manufacturer: Parallax Inc

Specifications of 28122

• Accessory Type: Parts Kit
• Product: Microcontroller Accessories
• Core Processor: PIC16C57c
• Flash: 128 Bytes
• Operating Supply Voltage: 9 V
• Board Size: 31 mm x 16 mm
• For Use With/related Products: Board of Education Full Kit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Figure 6-3 shows a schematic of the LEDs inside the 7-segment LED display. Each LED
anode is connected to an individual pin. All the cathodes are connected together by wire
inside the part. Because all the cathodes share a common connection, the 7-segment LED
display can be called a “common cathode” display. By connecting either pin 3 or pin 8 of
the part to Vss, you will connect all the LED cathodes to Vss.
Pin Map: Figure 6-2 is an example of a pin map. A pin map contains useful information that
helps you connect a part to other circuits. Pin maps usually show a number for each pin, a
name for each pin, and a reference. Take a look at Figure 6-2. Each pin is numbered, and
the name for each pin is the segment letter next to the pin. The reference for this part is its
overall appearance. You know by looking at the top of the display that pin 1 is closest to the
lower-left corner of the display. Other parts have more subtle references, such as the flat
spot on a regular LED’s case.
10 9
1 2
G F
E D
E
F
Common
Common
Cathode
Cathode
D
8
3
G
A
7 6
4 5
C
A B
C DP
B
Figure 6-2
7-Segment
LED Display
Part Drawing
and Pin Map