MC68HC08LT8 Datasheet, PDF (75/156 Pages) Freescale Semiconductor, Inc – Microcontrollers

Chapter 8
Liquid Crystal Display (LCD) Driver
8.1 Introduction
This section describes the liquid crystal display (LCD) driver module. The LCD driver module can drive a
maximum of 25 frontplanes and 4 backplanes, depending on the LCD duty selected.
8.2 Features
Features of the LCD driver module include the following:
• Software programmable driver segment configurations:
– 24 frontplanes × 4 backplanes (96 segments)
– 25 frontplanes × 3 backplanes (75 segments)
– 25 frontplanes × 1 backplane (25 segments)
• LCD bias voltages generated by internal resistor ladder
• Software programmable contrast control
8.3 Pin Name Conventions and I/O Register Addresses
Three dedicated I/O pins are for the backplanes, BP0–BP2; twenty four frontplanes, FP1–FP24, are
shared with port B, C, D, and E pins. FP0 and BP3 shares the same pin and configured by the DUTY[1:0]
bits in the LCD clock register.
The full names of the LCD output pins are shown in Table 8-1. The generic pin names appear in the text
that follows.
Table 8-1. Pin Name Conventions
LCD Generic Pin Name
FP0/BP3
BP0–BP2
FP1–FP2
FP3–FP10
FP11–FP18
FP19–FP24
Full MCU Pin Name
FP0/BP3
BP0–BP2
PTB6/FP1–PTB7/FP2
PTE0/FP3–PTE7/FP10
PTD0/FP11–PTD7/FP18
PTC0/FP19–PTC5/FP24
Pin Selected for LCD Function by:
—
—
LCDE in LCDCR
PEE in CONFIG2
LCDE in LCDCR
PDE in CONFIG2
LCDE in LCDCR
PCEL:PCEH in CONFIG2
LCDE in LCDCR
MC68HC08LT8 Data Sheet, Rev. 1
Freescale Semiconductor
75