tda9950 NXP Semiconductors, tda9950 Datasheet - Page 14

• Manufacturer Part Number: tda9950
• Description: Tda9950 Cec/i?c-bus Translator
• Manufacturer: NXP Semiconductors

NXP Semiconductors
TDA9950_1
Product data sheet
8.7.2 Sending a CEC message
8.7.3 Receiving a CEC message
Example: the host processor of Playback Device 1 (see HDMI1.3a specification) or DVD1
(see HDMI1.2a specification) wishes to send the message <TextView On> to TV:
Example: TV sends the message <Give Physical Address> to Playback Device 1 (see
HDMI1.3a specification) or DVD1 (see HDMI1.2a specification):
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The TDA9950 is now enabled. Messages addressed to logical address Tuner 1 (see
HDMI1.3a specification) or STB1 (see HDMI1.2a specification) will be acknowledged
and forwarded to the host processor.
I2C_WRITE: 00h; I2C_READ, I2C_READ, ....
Set Address Pointer to 00h (CSR), read TDA9950 Status Register - repeat read until
TDA9950 is no longer busy (bit CSR[7] = 0).
I2C_WRITE: 07h, 04h, 00h, 40h, 0Dh
Set Address Pointer to 07h (CEC Data Register 1), write CEC Data Registers.
FrameByteCount = 4, ServiceSelector = CECData.req, AddressByte = DVD/TV,
DataByte = <TextView On>.
Wait for INT line to be asserted
When TDA9950 has a response, it will assert the INT line (the host could also poll bit
CSR[6]).
I2C_WRITE: 07h; I2C_READ: 03h, 01h, 00h
Set Address Pointer to 07h (Data Register 1), read CEC Data Registers.
FrameByteCount = 3, ServiceSelector = CECData.cnf, ResultCode = Success.
INT line is asserted
The TDA9950 at Playback Device 1 (see HDMI1.3a specification) or DVD1 (see
HDMI1.2a specification) has acknowledged the message from TV and it is now
available for reading by the Playback Device 1 (see HDMI1.3a specification) or DVD1
(see HDMI1.2a specification) host processor.
I2C_WRITE: 07h; I2C_READ: 04h, 81h, 04h, 83h
Set Address Pointer to 07h (Data Register 1), read CEC Data Registers.
FrameByteCount = 4, ServiceSelector = CECData.ind, AddressByte = TV/DVD,
DataByte = <Give Physical Address>.
Rev. 01 — 16 November 2007
CEC/I
TDA9950
© NXP B.V. 2007. All rights reserved.
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C-bus translator
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