PCF2114 Просмотр технического описания (PDF) - Philips Electronics

Номер в каталоге

Компоненты Описание

производитель

PCF2114

LCD controller/drivers

Philips Electronics 

Philips Semiconductors

LCD controller/drivers

Product specification

PCF2116 family

8.18 Programming MUX 1 : 32 displays with the

PCF2114x

To drive a 2-line by 24 characters MUX 1 : 32 display, use

instruction ‘Function set’ M, N to 0, 1. Note that the right

half of the display needs mirrored column connection

compared to a display driven by a PCF2116x.

To drive a 4-line by 12 characters MUX 1 : 32 display the

PCF2116x operating instructions apply. There is no

functional difference between the PCF2114x and the

PCF2116x in this mode. For such an application

set M, N to 1, 1 with the ‘Function set’ instruction.

8.19 Reset function

The PCF2116 automatically initializes (resets) when

power is turned on. After reset the chip has the following

state.

Table 2 State after reset

STEP

DESCRIPTION

1 display clear

2 function set

DL = 1 8-bit interface

M, N = 0 1-line display

G=0

3 display on/off D = 0

control

C=0

voltage

generator;

VLCD = V0

display off

cursor off

B = 0 blink off

4 entry mode set I/D = 1 +1 (increment)

S = 0 no shift

5 Default address pointer to DDRAM. The Busy

Flag (BF) indicates the busy state (BF = logic 1)

until initialization ends. The busy state lasts

2 ms. The chip may also be initialized by

software. See Figs 28 and 29.

6 I2C-bus interface reset

9 INSTRUCTIONS

Only two PCF2116 registers, the Instruction Register (IR)

and the Data Register (DR) can be directly controlled by

the microcontroller. Before internal operation, control

information is stored temporarily in these registers to allow

interface to various types of microcontrollers which

operate at different speeds or to allow interface to

peripheral control ICs.

The PCF2116 operation is controlled by the instructions

shown in Table 3 together with their execution time.

Details are explained in subsequent sections.

Instructions are of 4 categories, those that:

1. Designate PCF2116 functions such as display format,

data length, etc.

2. Set internal RAM addresses

3. Perform data transfer with internal RAM

4. Others.

In normal use, category 3 instructions are used most

frequently. However, automatic incrementing by 1 (or

decrementing by 1) of internal RAM addresses after each

data write lessens the microcontroller program load. The

display shift in particular can be performed concurrently

with display data write, enabling the designer to develop

systems in minimum time with maximum programming

efficiency.

During internal operation, no instruction other than

‘Read busy flag and address’ will be executed.

Because the Busy Flag is set to logic 1 while an instruction

is being executed, check to make sure it is on logic 0

before sending the next instruction or wait for the

maximum instruction execution time, as given in Table 3.

An instruction sent while the Busy Flag is HIGH will not be

executed.

1997 Apr 07

22

Share Link: