PIC16F877-20I/PT Microchip Technology, PIC16F877-20I/PT Datasheet - Page 482

• Manufacturer Part Number: PIC16F877-20I/PT
• Description: IC MCU FLASH 8KX14 EE 44TQFP
• Manufacturer: Microchip Technology
• Series: PIC® 16Fr

Specifications of PIC16F877-20I/PT

• Program Memory Type: FLASH
• Program Memory Size: 14KB (8K x 14)
• Package / Case: 44-TQFP, 44-VQFP
• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 33
• Eeprom Size: 256 x 8
• Ram Size: 368 x 8
• Voltage - Supply (vcc/vdd): 4 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Processor Series: PIC16F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 368 B
• Interface Type: MSSP/PSP/USART
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 33
• Number Of Timers: 3
• Operating Supply Voltage: 2 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: 52715-96, 52716-328, 52717-734
• Development Tools By Supplier: PG164130, DV164035, DV244005, DV164005, PG164120, ICE2000, DM163022, DV164120
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 8-ch x 10-bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: XLT44PT3 - SOCKET TRAN ICE 44MQFP/TQFPAC164305 - MODULE SKT FOR PM3 44TQFP444-1001 - DEMO BOARD FOR PICMICRO MCUAC164020 - MODULE SKT PROMATEII 44TQFP
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

PICmicro MID-RANGE MCU FAMILY
25.15
DS31025A-page 25-24
Design Tips
Question 1:
Answer 1:
Ensure that you have the control bits in the LCDSE properly configured, since these bits override
the TRIS bits.
Question 2:
Answer 2:
Your frame frequency may be too low. The frame frequency can be changed in the LCDPS
register.
Question 3:
Answer 3:
This may be due to misadjusted LCD voltage, some possibilities include:
1.
2.
If you are using the R-ladder, try different values of R, vary the R-ladder potentiometer.
The VLCDADJ pin should be connected to ground.
If you are using the charge pump, adjust the resistance value on the VLCDADJ pin.
I’m trying to use some of the LCD pins as inputs.
My LCD panel is flickering.
The LCD segments are not very visible.
1997 Microchip Technology Inc.