
Z86129/130/131
NTSC Line 21 Decoder
P R E L I M I N A R Y
DS96TEL0200
45
1
General Commands
Caption/text Display Mode Commands
CPTX = 10h-1Fh.
Caption and Text display mode
commands. These commands select the desired Line 21
data stream (Closed Caption or Text) for display. See the
Commands
section for a complete description of the
CPTX Display Mode command.
Caption and Text display commands are one byte
commands. A data channel can be selected for display
with the display either enabled (DEC ON) or disabled
(DEC OFF). All these commands will turn off an active
XDS display mode. The following table summarizes the
device’s Caption and Text display modes and the proper
command code to activate them
XDS Display Mode and 16 Second Erase Tim-
er Commands
XDS DISP = 20h-27h.
XDS Display commands are one
byte commands. These commands control the selection of
XDS display modes and the state of the 16 Second Erase
Timer. The 16 Second Erase Timer is active only for
Caption and XDS display modes. The 16 Second Erase
Timer has no affect on TEXT mode displays.
SCRIPTI Program
This program is designed to send any number of one or
two byte commands to the Z86129. The list of commands
to be executed are contained in Script files that have the
extension.SER. Examples of such files will be presented in
the following paragraphs. SCRIPTI can be used to control
the display modes in the same manner as the IICO
program except that the one byte command to be sent
must be in a Script file. For example a file called CC1.SER
would contain the one byte command:
{17}*
send CC1, decoder ON
The program is invoked by typing:
SI File_name<ENTER>
Note:
File_name without the .SER extension
The screen will display:
EEG CCD2 Serial Interface Script Player Version x.xx
Slave Address is 28h
Script File Done
The responding slave address is reported to the screen.
When all the commands in the file have been successfully
sent to the Z86129, the PC will return to the system
prompt.
The program checks the RDY status before sending each
byte. If, during the entry of a command, the RDY bit is not
found to be a "one" after an extended wait, the program will
report the contents of the SS register and then continue
checking for RDY.
Serial Cmd
RESET
NOP
SSB
Cmd Code
FBh, FCh, 00h
00h
FFh,...FFh,FEh
Figure 29. CPTX - Caption/Text Display
(CPTX = 10h-1Fh)
CPTX
Command
CC1
CC2
CC3
CC4
T1
T2
T3
T4
CPTX Command Code
Decoder ON
17h
15h
1Fh
1Dh
13h
11h
1Bh
19h
Decoder OFF
16h
14h
1Eh
1Ch
12h
10h
1A
18
Bit
0
0
R/W
R/W
R/W
0
CM7
CM6
CM5
CM4
CM3
CM2
CM1
CM0
1
LANG CPTX DONOF
R/W
R/W
R/W
R/W
R/W
FLD
XDS Display
Command
XDSG
XDSF
16 SECOND
ERASE TIMER
XDS Display Command Code
16 Sec Tmr ON
23h
21h
16 Sec Tmr OFF
27h
25h
20h
24h
Note:
Changing the ON/OFF state of the 16 Second Erase Tim-
er has no affect on the current display mode in operation.