ADE7169F16 datasheet(95/140 Pages) AD

95 / 140 page

Preliminary Technical Data

ADE7169F16

Rev. PrD | Page 95 of 140

(LCDCON, 0x95) control LCD functionality in the PSM2

operating mode.

LCDPSM2

LCDEN

Comments

The display is OFF in PSM2.

The display is ON in PSM2.

The display is OFF in PSM2.

Note that the LCD configuration and data memory is retained

when the display is turned off.

EXAMPLE LCD SETUP

An example to set up the LCD peripheral for a specific LCD is

described below.

Type of LCD: 5V, 4x multiplexed with 1/3 bias, 96 segments

Voltage Generation: Internal Charge Pump

Refresh Rate: 64Hz

A 96 segment LCD with 4x multiplexing requires 96/4=24

segment lines. There are 16 pins that automatically dedicated

for use as LCD segments, FP0 to FP15. Eight more pins must be

chosen for the LCD function. Since the LCD has 4x

multiplexing, all four common lines are used so COM2/FP28

and COM3/FP27 cannot be utilized as segment lines. Based on

the alternate functions of the pins used for FP16 through FP25,

FP16-23 are chosen for the seven remaining segment lines.

These pins will be enabled for LCD functionality in the LCD

Segment Enable SFR (LCDSEGE, 0x97) and LCD Segment

Enable 2 SFR (LCDSEGE2, 0xED).

To determine contrast setting for this 5V LCD, look in Table 73

to find the BIASLVL[5:0] setting that corresponds to a VC of 5V

in 1/3 Bias Mode. The nominal bias level setting for this LCD is

BIASLVL[5:0]=[111111].

The LCD is setup with the following 8052 code:

; setup LCD pins to have LCD functionality

MOV

LCDSEG, # FP20EN+FP21EN+FP22EN+FP23EN

MOV

LCDSEGX, #FP16EN+FP17EN+FP18EN+FP19EN

; setup LCDCON for fLCDCLK=2048Hz, 1/3 bias and 4x multiplexing

MOV

LCDCON, #BIAS+LMUX1+LMUX0

; setup LCDCONX for charge pump and BIASLVL[1110111]

MOV

LCDCONX, #BIASLVL5+BIASLVL4+BIASLVL3+

BIASLVL2+BIASLVL1+BIASLVL0

; set up refresh rate for 64Hz with fLCDCLK=2048Hz, from

Table 76

MOV

LCDCLK, #FD3+FD2+FD1+FD0

; set up LCD data registers with data to be displayed using

; LCDPTR and LCDDATA registers

; turn all segments on FP25 ON and FP26 OFF

ORL

LCDCONY,#01h

; start data memory refresh

MOV

LCDDAT, #F0H

MOV

LCDPTR, #80h OR 0DH

ANL

LCDCONY,#0FEh

; end of data memory refresh

ORL

LCDCON,#LCDEN ; enable LCD

To setup the same 3.3V LCD for use with an external resistor

ladder:

; setup LCD pins to have LCD functionality

MOV

LCDSEG, #FP20EN+FP21EN+FP22EN+FP23EN

MOV