STV2050A datasheet(16/83 Pages) STMICROELECTRONICS

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STV2050A - SLAVE I²C BUS INTERFACE

If the autoincrement function is enabled, the internal address is automatically incremented

after 3 bytes are either written or read. When the autoincrement counter reaches the CF ad-

dress, the counter stops counting and any additional data will be written to or read from the CF

address.

3.2 COLOR BANK SELECTION

As previously mentioned, the embedded RAM is mapped in 3 banks called the “Red and I²C

Bank”, “Green Bank” and the “Blue Bank”. A bank is selected using the CBS[1:0] (Color Bank

Selection) bits located in the E7 register address.

However, sub-addresses D0 to EF and FE (physically mapped in the “Red and I²C Bank”) are

independent of the actual bank selection.

3.3 WRITE COMMANDS

Three formats of write commands are supported:

– 5-byte write commands to any valid sub-address

S DW SA D0 D1 D2 P

If the auto-increment function is enabled, the internal address is at SA+1 after the command,

otherwise it is still at SA.

– 2-byte write commands for defining a sub-address cursor position or for changing the

current sub-address without transmitting data.

S DW SA P

The sub-address is at SA after the command.

– Auto-increment write commands for sub-address range 00 to CF

If the auto-increment function is enabled, the internal address counter is incremented each

time 3 bytes are written:

S DW SAi Di0 Di1 Di2 Di+10 Di+11 Di+12... Dn P

otherwise every group of 3 bytes is written to SA and the sub-address does not change.

S DW SAi Di0 Di1 Di2 Di0 Di1 Di2... ... Dn P

When a group of three data bytes within the 00 to E2 address range has been received, the

slave will store them in the appropriate embedded RAM location. Only complete groups of

three data bytes are stored. I²C registers start to be updated when the first data byte is re-

ceived. Only complete bytes are written.

All write commands which do not comply with the formats described above are rejected.

CBS[1:0]

00 = Red and I²C bank selected

01 = Green bank selected

10 = Blue bank selected

11 = Red and I²C bank selected

STV2050A Datasheet(PDF) 16 Page - STMicroelectronics