HDMI 1.4/2.0 TX Subsystem
86
PG235 October 4, 2017
Appendix
B:
Debugging
• The interface is enabled, and
s_axi_aclken
is active-High (if used).
• The main subsystem clocks are toggling and that the enables are also asserted.
• Add AXI4 Lite interface to ILA, and analysis data captured when triggering at
s_axi_rvalid
.
AXI4-Stream Interfaces
If data is not being transmitted or received, check the following conditions:
• If received <interface_name>_tready is stuck low, the subsystem cannot send data.
Check if there is an issue at the AXI4 Stream Slave.
• Check that the
aclk
inputs are connected and toggling.
• Check that the AXI4-Stream waveforms are being followed.
• Check subsystem configuration.
AXI4-Stream Audio Interface
To ensure that the audio is working in HDMI 1.4/2.0 Transmitter Subsystem, the
AXI4-Stream must be constructed as described below.
The HDMI 1.4/2.0 Transmitter Subsystem supports up to 8 audio channels. The audio data
is transmitted through AXI4-Stream audio interface, which is a customized AXI4-Stream
protocol that is used to send audio samples with sideband signals defined in AES3
specification.
The sub-frame format for audio sample is shown as below.
A frame is uniquely composed of two sub-frames. The first sub-frame normally starts with
preamble "X", and the second sub-frame always starts with preamble “Y”. However, every
192 frames form one “Audio Block”. And the first sub-frame in each “Audio Block” starts with
a preamble “Z”. An illustration is shown below.
X-Ref Target - Figure B-1
X-Ref Target - Figure B-2