Z86130 ZILOG [Zilog, Inc.], Z86130 Datasheet - Page 23

• Manufacturer Part Number: Z86130
• Description: NTSC LINE 21 DECIDER
• Manufacturer: ZILOG [Zilog, Inc.]

the write of the READ1 or READ2 command. The data
byte or bytes are then clocked-out in sequence, MSB first,
while NOP commands are written into the device. Data bits
are clocked-out on the rising edge of SCK. All available
data bytes must be read to clear the DAV bit and permit
subsequent reads.
The SPI Bus Protocol
1. The first bit of the first output byte is driven out on SDO
2. Three-wire bus with Clock signal on SCK pin, Serial
COMMANDS
Serial Port Commands
The majority of the Z86129/130/131 commands are
common to both the I
the commands must be contained within the Start-Slave
Address-etc. sequence.
Note: In the following Command descriptions, the letter 'h'
following a command code designates Hexadecimal
notation.
Reset
RESET = FBh, FCh, 00h. RESET is a three byte
command sequence in SPI or I
command will establish all the specified default settings in
the device, but it will not reset the serial port itself. This
sequence can be entered without RDY being set.
No Operation
NOP = 00h. NOP is a one-byte command for use in SPI or
I
of the RDY bit in the Serial Status (SS) register and can be
executed independent of the RDY status.
Serial Sync Bytes
SSB = FFh,....,FFh,FEh. Serial Sync Bytes are used in
SPI mode only. This command actually consists of a string
of single-byte commands in the form FFh,....FFh,FEh. SPI
mode communications can be synchronized by sending a
synchronizing data string to the part. This string should
consist of at least two SSB bytes of FFh followed by one
DS96TEL0200
2
C mode. The NOP command does not affect the status
following the rising edge of SCK on the last bit (LSB)
of the READ1 or READ2 command.
Data Input on SDA pin and Serial Data Output on SDO
pin.
2
C and SPI modes. In the I
2
C mode. The RESET
2
P R E L I M I N A R Y
C mode,
3. SEN pin Low disabled the port, placing SDO in tri-
4. SEN pin High enables the port for operation.
5. SEN and SMS pins Low is a hardware reset for the
6. Serial synchronization can be established by clocking
SSB byte of FEh. At the end of the FEh byte the port is
ready for use.
Serial Command Command Code
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.
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. Table 9 summarizes the device’s
Bit
state. Signal transitions on SCK and SDA are ignored.
part. These pins must be held Low for at least 100 ns.
in the minimum required SSR string of FFh, FFh, FEh.
More than two bytes of FFh may be input but the string
must end with FEh.
CM7
R/W
RESET
0
NOP
SSB
Figure 12. CPTX-Caption/Text Display
Table 8. Basic Serial Commands
CM6
R/W
0
CM5
R/W
(CPTX = 10h-1Fh)
0
FFh,...FFh,FEh
FBh, FCh, 00h
CM4
R/W
00h
1
CM3
R/W
FLD
NTSC Line 21 Decoder
LANG CPTX DONOF
CM2
R/W
SPI mode only
Z86129/130/131
SPI or I
SPI or I
Notes
CM1
R/W
2
2
C
C
R/W
CM0
23
1