Chameleon-AVR Nurve Networks, Chameleon-AVR Datasheet - Page 47

• Manufacturer Part Number: Chameleon-AVR
• Description: MCU, MPU & DSP Development Tools AVR8 & PROPELLER DEV SYSTEM (SBC)
• Manufacturer: Nurve Networks

Specifications of Chameleon-AVR

• Processor To Be Evaluated: AVR 328P
• Data Bus Width: 8 bit
• Interface Type: USB, VGA, PS/2, I2C, ISP, SPI
• Operating Supply Voltage: 3.3 V, 5 V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

11.2.2 Video Formats and Interfaces
There are many different kinds of video signals, which can be divided into either two classes; those for television and
those for computer displays. The format of television signals varies from country to country. In the United States and
Japan, the NTSC format is used. NTSC stands for National Television Systems Committee, which is the name of the
organization that developed the standard. In Europe, the PAL format is common. PAL (phase alternating line), developed
after NTSC, is an improvement over NTSC. SECAM is used in France and stands for sequential coleur avec memoire
(color with memory). It should be noted that there is a total of about 15 different sub-formats contained within these three
general formats. Each of the formats is generally not compatible with the others. Although they all utilize the same basic
scanning system and represent color with a type of phase modulation, they differ in specific scanning frequencies, number
of scan lines, and color modulation techniques, among others. The various computer formats (such as VGA, SVGA, XGA)
also differ substantially, with the primary difference in the scan frequencies and resolutions. These differences do not
cause as much concern, because most computer equipment is now designed to handle variable scan rates (multisync
monitors are now the de-facto standard). This compatibility is a major advantage for computer formats in that media, and
content can be interchanged on a global basis. Table 11.2 lists some of the more popular formats along with comparisons
of their specifications.
Description
Vertical Resolution
Format (visible
lines per frame)
Horizontal
Resolution Format
(visible pixels per
line)
Horizontal Rate
(kHz)
Vertical Frame
Rate (Hz)
Highest
Frequency (MHz)
Of course, not listed in the table are HDMI video modes. These are a whole other ballgame, but are very similar to XGA
modes and higher.
11.2.3. Composite Color Video Blanking Sync Interface
Composite signals are the most commonly used analog video interface for NTSC/PAL. Composite video is also referred to
as CVBS, which stands for color, video, blanking, and sync, or composite video baseband signal. It combines the
brightness information (luma), the color information (chroma), and the synchronizing signals on just one cable. The
connector is typically an RCA jack. This is the same connector as that used for standard line level audio connections. S-
video of course is slightly cleaner since the analog mixing of chroma and luma does NOT take place. A typical waveform
of an all-white NTSC composite video signal is shown in Figure 11.5 (a).
Video Format
Table 11.2 - Typical Frequencies for Common TV and Computer Video Formats.
bandwidth, ranges
Television Format
for North America
Approx 480 (525
from 320 to 650
Determined by
and Japan
total lines)
15.734
NTSC
29.97
4.2
and South America
for Most of Europe
bandwidth, ranges
Television Format
Approx 575 (625
from 320 to 720
Determined by
total lines)
15.625
PAL
5.5
25
1080 or 720 or 480;
1920 or 704 or 640;
18 different formats
18 different formats
Standard Definition
Digital Television
High Definition/
© 2009 NURVE NETWORKS LLC “Exploring the Chameleon AVR 8-Bit”
HDTV/SDTV
33.75-45
Format
30-60
25
Array (PC)
Graphics
Video
60-80
VGA
31.5
15.3
480
640
Array (PC)
Extended
Graphics
60-80
1024
XGA
40.7
768
60
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