Difference between revisions of "Protocol decoder:Cec"
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'''Print all annotations (very verbose)''' | '''Print all annotations (very verbose)''' | ||
'''sigrok-cli -i data.sr -P cec:CEC=CEC'' | '''sigrok-cli -i data.sr -P cec:CEC=CEC''' | ||
cec-1: ST | cec-1: ST |
Revision as of 18:26, 3 November 2019
File:Cec hdmi pinout.png | |
Name | cec |
---|---|
Description | HDMI Consumer Electronics Control (CEC) protocol. |
Status | supported |
License | GPLv2+ |
Source code | decoders/cec |
Input | logic |
Output | cec |
Probes | cec |
Consumer Electronics Control (CEC) is a feature of HDMI designed to allow users to command and control devices connected through HDMI
Hardware
CEC Bus can be found in PIN 13 of the HDMI connector:
Protocol
It is a one-wire bidirectional serial bus that is based on the CENELEC standard AV.link protocol to perform remote control functions.
CEC is a separate electrical signal from the other HDMI signals. This allows a device to disable its high-speed HDMI circuitry in sleep mode, but be woken up by CEC. It is a single shared bus, which is directly connected between all HDMI ports on a device, so it can flow through a device which is completely powered off (not just asleep).
The bus is electrically identical to the AV.link protocol, but CEC adds a detailed higher-level message protocol.
The bus is an open-collector line, somewhat like I²C, passively pulled up to +3.3 V, and driven low to transmit a bit.
Pulseview screenshots
Usage examples
Print all annotations (very verbose)
sigrok-cli -i data.sr -P cec:CEC=CEC cec-1: ST cec-1: 0 cec-1: 0 cec-1: 1 cec-1: 1 cec-1: 0 cec-1: 0 cec-1: 0 cec-1: 0 cec-1: 0x30 cec-1: EOM=N cec-1: ACK cec-1: 0 cec-1: 0 cec-1: 0 cec-1: 0 cec-1: 0 cec-1: 1 cec-1: 0 cec-1: 0 cec-1: 0x04 cec-1: EOM=Y cec-1: ACK cec-1: 30:04 cec-1: HDR: Tuner_1, TV | OPC: IMAGE_VIEW_ON | R: ACK
Print frames only
sigrok-cli -i data.sr -P cec:CEC=CEC -A cec=frames cec-1: 30:04 cec-1: 35 cec-1: 35 cec-1: 3f:82:10:00 cec-1: 30:8f cec-1: 03:90:01 cec-1: 30:44:6d cec-1: 35 cec-1: 35 cec-1: 30:04 cec-1: 35 cec-1: 35 cec-1: 30:0d cec-1: 35 cec-1: 35 cec-1: 35 cec-1: 35 cec-1: 30:04 cec-1: 35 cec-1: 35 cec-1: 30:8f cec-1: 03:90:01 cec-1: 35 cec-1: 35 cec-1: 35 cec-1: 35 cec-1: 35 cec-1: 35 cec-1: 30:04
Print sections only
sigrok-cli -i data.sr -P cec:CEC=CEC -A cec=sections cec-1: HDR: Tuner_1, TV | OPC: IMAGE_VIEW_ON | R: ACK cec-1: HDR: Tuner_1, AudioSystem | OPC: PING | R: NACK cec-1: HDR: Tuner_1, AudioSystem | OPC: PING | R: NACK cec-1: HDR: Tuner_1, Broadcast | OPC: ACTIVE_SOURCE | OPS: 0x10, 0x00 | R: ACK cec-1: HDR: Tuner_1, TV | OPC: GIVE_DEVICE_POWER_STATUS | R: ACK cec-1: HDR: TV, Tuner_1 | OPC: REPORT_POWER_STATUS | OPS: 0x01 | R: ACK cec-1: HDR: Tuner_1, TV | OPC: USER_CONTROL_PRESSED | OPS: 0x6d | R: ACK cec-1: HDR: Tuner_1, AudioSystem | OPC: PING | R: NACK cec-1: HDR: Tuner_1, AudioSystem | OPC: PING | R: NACK cec-1: HDR: Tuner_1, TV | OPC: IMAGE_VIEW_ON | R: ACK cec-1: HDR: Tuner_1, AudioSystem | OPC: PING | R: NACK cec-1: HDR: Tuner_1, AudioSystem | OPC: PING | R: NACK cec-1: HDR: Tuner_1, TV | OPC: TEXT_VIEW_ON | R: ACK cec-1: HDR: Tuner_1, AudioSystem | OPC: PING | R: NACK cec-1: HDR: Tuner_1, AudioSystem | OPC: PING | R: NACK cec-1: HDR: Tuner_1, AudioSystem | OPC: PING | R: NACK cec-1: HDR: Tuner_1, AudioSystem | OPC: PING | R: NACK cec-1: HDR: Tuner_1, TV | OPC: IMAGE_VIEW_ON | R: ACK cec-1: HDR: Tuner_1, AudioSystem | OPC: PING | R: NACK cec-1: HDR: Tuner_1, AudioSystem | OPC: PING | R: NACK cec-1: HDR: Tuner_1, TV | OPC: GIVE_DEVICE_POWER_STATUS | R: ACK cec-1: HDR: TV, Tuner_1 | OPC: REPORT_POWER_STATUS | OPS: 0x01 | R: ACK cec-1: HDR: Tuner_1, AudioSystem | OPC: PING | R: NACK cec-1: HDR: Tuner_1, AudioSystem | OPC: PING | R: NACK cec-1: HDR: Tuner_1, AudioSystem | OPC: PING | R: NACK cec-1: HDR: Tuner_1, AudioSystem | OPC: PING | R: NACK cec-1: HDR: Tuner_1, AudioSystem | OPC: PING | R: NACK cec-1: HDR: Tuner_1, AudioSystem | OPC: PING | R: NACK cec-1: HDR: Tuner_1, TV | OPC: IMAGE_VIEW_ON | R: ACK cec-1: HDR: Tuner_1, AudioSystem | OPC: PING | R: NACK cec-1: HDR: Tuner_1, AudioSystem | OPC: PING | R: NACK cec-1: HDR: Tuner_1, TV | OPC: GIVE_DEVICE_POWER_STATUS | R: ACK cec-1: HDR: TV, Tuner_1 | OPC: REPORT_POWER_STATUS | OPS: 0x01 | R: ACK