Z86230 Datasheet, PDF (23/61 Pages) Zilog, Inc. – ADVANCED VIOLENCE BLOCKING AND NTSC 21 XDS

SERIAL PORT COMMANDS
COMMANDS
5. COMMANDS
5.1 SERIAL PORT COMMANDS
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.
5.1.1 RESET = FBh
RESET is a 1-byte command. The RESET command establishes all of the speci-
fied default settings in the device, but it does not reset the serial port itself. The
RESET command must be followed by a no operation (NOP) command, because
RESET stays active until deactivated by the NOP. This sequence can be entered
without the RDY bit being set.
5.1.2 NOP = 00h
NOP is a 1-byte command. The NOP command does not affect the status of the
RDY bit in the Serial Status Register (SSR) and can be executed independent of
the RDY status.
TABLE 7. BASIC SERIAL COMMANDS
Serial Command
RESET
NOP
Command Code
FBh
00h
5.2 READ AND WRITE COMMANDS
All register diagrams indicated in this section incorporate the following conven-
tions, unless otherwise noted:
• R = Read, W = Write, X = Indeterminate, and res = Reserved
• All register bits marked as res must be set to Low(0)
5.2.1 READ Bank Select (RBS = FDh)
RDS1 is a 2-byte command to select the read data bank. The lower 2 bits of the
second data byte select one of four banks of up to 33 bytes. A subsequent I²C
READ deciphers data from the specified bank.
5.2.2 READ SELECTs (RDS1 = 40h–51H)
RDS1 is a 1-byte command used to initiate a 1-byte READ sequence. This activity
is performed by moving the contents of the register identified by the address field
(AD00:04) of the command to the first location of READ bank 0. Addresses 00h–
11h are valid in the RDS1 command field AD00:04.
PS000400-TVC0499
Z86230—PRELIMINARY
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