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ORLDWIDE
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EADQUARTERS
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A
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Z90255 ROM and Z90251 OTP
32 KB Television Controller
with OSD
Product Specification
PS001301-0800
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whether a later edition exists, or to request copies of publications, contact
ZiLOG Worldwide Headquarters
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Fax: 408.558.8300
www.ZiLOG.com
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Z90255 ROM and Z90251 OTP
32 KB Television Controller with OSD
PS001301-0800
iii
Table of Contents
1
Overview 1
1.1
Pin Assignment and Descriptions .................................................... 5
1.2
Single-Purpose Pin Descriptions ..................................................... 7
1.3
Multiplexed Pin Descriptions............................................................ 8
2
Memory Description ........................................................................ 10
2.1
Standard Register File ................................................................... 10
2.2
Expanded Register File ................................................................. 11
2.3
Program Memory ........................................................................... 11
3
Watch-Dog Timer (WDT) ................................................................ 15
4
Stop Mode and Halt Mode Operation .............................................. 16
4.1
Power-Down Halt-Mode Operation ................................................ 16
4.2
Stop Mode Operation ..................................................................... 17
4.3
STOP Mode Recovery Register .................................................... 18
5
On-Screen Display .......................................................................... 22
5.1
OSD Position ................................................................................. 22
5.2
Second Color Feature.................................................................... 25
5.3
Mesh and Halftone Effect .............................................................. 28
5.4
OSD Fade ...................................................................................... 33
5.5
Inter-Row Spacing ......................................................................... 36
5.6
Character Generation .................................................................... 37
5.7
Character Size and Smoothing Effect ............................................ 39
5.8
Fringing Effect................................................................................ 40
5.9
Display Attribute Control ................................................................ 40
5.10
HV Interrupt Processing ................................................................. 49
6
Z90255 I2C Master Interface .......................................................... 53
7
Input/Output Ports ........................................................................... 57
7.1
Port 4 Pin-Out Selection Register.................................................. 59
7.2
Port 5 Pin-Out Selection Register .................................................. 62
7.3
Port 6 Data Register ...................................................................... 63
8
Infrared Interface ............................................................................. 65
Z90255 ROM and Z90251 OTP
32 KB Television Controller with OSD
PS001301-0800
iv
9
Pulse Width Modulators .................................................................. 68
9.1
PWM Mode Register ...................................................................... 68
9.2
PWM1 through PWM11 ................................................................. 70
9.3
Digital/Analog Conversion with PWM ............................................ 79
10
Analog-to-Digital Converter ............................................................. 80
11
Electrical Characteristics ................................................................. 83
11.1
Absolute Maximum Ratings ............................................................ 83
11.2
DC Characteristics ......................................................................... 84
11.3
AC Characteristics ......................................................................... 85
11.4
Timing Diagram ............................................................................. 86
12
Packaging ....................................................................................... 87
Ordering Information ....................................................................... 88
ROM Code Submission ................................................................... 88
Customer Feedback Form .............................................................. 89
Z90255 ROM and Z90251 OTP
32 KB Television Controller with OSD
PS001301-0800
v
List of Figures
1
Z90255-Based TV System Application ........................................................ 2
2
Z90255 Block Diagram ................................................................................ 3
3
Z90255 and Z90251 Pin Assignments......................................................... 5
4
Code Development Environment ............................................................... 10
5
Register File Map....................................................................................... 12
6
Program Memory Map ............................................................................... 14
7
Stop Mode Recovery Source/Level Select ................................................ 21
8
Positive and Negative Sync Signals .......................................................... 23
9
Second Color Display ................................................................................ 28
10
Mesh On .................................................................................................... 29
11
Video Fade (Example) ............................................................................... 34
12
Character Pixel map in CGROM................................................................ 37
13
Example of a Multiple Character Icon ........................................................ 38
14
Smoothing Effect on 2X Character Size .................................................... 39
15
VRAM Data Path for 512 Character Set .................................................... 42
16
H
SYNC
and V
SYNC
Specification ............................................................... 52
17
Bidirectional Port Pin Pad Multiplexed with I2C Port ................................. 53
18
Pulse Width Modulator Timing Diagram, 6 Bit ........................................... 71
19
Pulse Width Modulator Timing Diagram, 14-Bit ......................................... 72
20
Analog Signals Generated from PWM Signals .......................................... 79
21
ADC Block Diagram ................................................................................... 82
22
Timing Requirements of External Inputs.................................................... 86
23
42-Lead Shrink Dual-in-line Package (SDIP) ............................................ 87
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