PCF8531U NXP [NXP Semiconductors], PCF8531U Datasheet - Page 19

• Manufacturer Part Number: PCF8531U
• Description: 34 x 128 pixel matrix driver
• Manufacturer: NXP [NXP Semiconductors]

NXP Semiconductors
9. Instructions
PCF8531_4
Product data sheet
9.2.1 PD
9.1 Reset
9.2 Function set
Only two PCF8531 registers, the Instruction Register (IR) and the Data Register (DR) can
be directly controlled by the MPU. Before internal operation, control information is stored
temporarily in these registers to allow interfacing to various types of MPUs which operate
at different speeds or to allow interfacing to peripheral control ICs. The PCF8531
operation is controlled by the instructions given in
Instructions are of four types:
In normal mode instructions which perform data transfer to/from the internal RAM are
used most frequently. Automatic incrementing by 1 of internal RAM addresses after each
data write reduces the MPU program load.
After reset or internal power-on reset (depending on the application), the LCD driver is set
to the following state:
When PD = 1, the Power-down mode of the LCD driver is active:
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Those that define PCF8531 functions e.g. display configuration, etc.
Those that set internal RAM addresses
Those that perform data transfer to/from the internal RAM
Others
Power-down mode (PD = 1)
Horizontal addressing (V = 0)
Display blank (D = 0; E = 0), no icon mode (IM = 0)
Address counter X[6:0] = 0; Y[2:0] = 0
Bias system BS[2:0] = 0
Multiplex rate M[1:0] = 0 (multiplex rate 1:17)
Temperature control mode TC[2:0] = 0
HV-gen control, HVE = 0 the HV generator is switched off, PRS = 0 and S[1:0] = 0
V
RAM data is undefined
Command page definition H[1:0] = 0
All LCD outputs at V
Power-on reset detection active, oscillator off
V
I
RAM contents not cleared; RAM data can be written
2
LCD
LCD
C-bus is operational, commands can be executed
= 0 V
can be disconnected
Rev. 04 — 13 June 2008
SS
(display off)
Table
11.
34 x 128 pixel matrix driver
PCF8531
© NXP B.V. 2008. All rights reserved.
19 of 44