How are you getting the capture from the HDHR to work?


I'm probably not emulating WNUV close enough. Especially using Transport Streams instead of IP packets. I'll guess the processing path for TS is quite a bit different than IP in the HDHomeRun.

Also, I don't have a universal frame mapper. I ...

I've added CTI to my open source ATSC 3.0 transmitter so that I could run some experiments. I've set up a flow that's similar to the WNUV configuration, but just TDM (not LDM+TDM). But I have used the same parameters for the low bitrate BPS PLP.

The low rate PLP works fine. The data comes out in ...

WNUV could use a 36 (PLP0 and 1) + 1 (PLP16) block HTI configuration and use more cells (and have a higher bitrate on PLP0 and 1) than they are with the CTI configuration.

I think the Sony demodulator is just sensitive to CTI configurations. I bet if they switched to HTI, it would all work. They're not using all the cells in their frame as it is (they're leaving 51257 cells unused), so the "we're able to maintain the efficiencies of CTI" argument is weak.

Some additional info. I can't even test multiple PLPs with CTI on my open source ATSC 3.0 transmitter. When I implemented multiple PLPs with TDM and FDM, I didn't include the CTI interleaver in the frame mapper. There were no multiple PLP test configurations from ATSC with CTI (there are 22 ...

This is just a guess, but I think some of these PLP 16 configurations are out of spec. Specifically, when there are two PLPs in a subframe using the CTI interleaver.

If you look at section 7.1.1 of A/322, it talks about what interleavers can be used. Unless you're using LDM, if there are multiple ...

I've added the bit-rate calculator to l1dump. Except for the L1_Basic FEC mode issue, it should be accurate for all modes. Sub-frames were a bit of a pain. I had to parse the L1 data twice to make it work.

Also, there's now an l1dump.h file. https://github.com/drmpeg/dtv-utils

This is great! I have a question though. I see in your collection of tools that you have an atsc3rate.c which appears to calculate the total bitrate for a PLP. Is the data necessary to use this present in the l1dump output? I eyeballed it and couldn't immediately verify all the parameters are ...

How to use the utility. First get the base64 string with hdhomerun_config.



Copy and paste the base64 string into a file with your favorite editor (for example, l1detail.txt). Then run the utility.

./l1dump l1detail.txt

Here's the C code.

https://github.com/drmpeg/dtv-utils/blob/master/l1dump.c

Some examples.

Two PLPs with TDM.

L1B_version = 0
L1B_mimo_scattered_pilot_encoding = Walsh-Hadamard pilots or no MIMO subframes
L1B_lls_flag = No LLS in current frame
L1B_time_info_flag = Time information is not ...

Ah, right...

The Sony demod driver returns the L1basic in a struct with everything split out. My tuner driver wrapper code puts it back together into the raw form before passing it to my ATSC 3 code. The CRC is the one thing that is missing so my conversion code sets it to zero.


Okay, no ...

I'm in the process of writing a parser for the new L1_Detail function. Is the L1_Basic CRC supposed to be all zeroes?

Here's the BASE64 string from the HDHomeRun.

ACHgAAAAADIAFcYgYMGH////////AAAAAAEjCABAAAABRSzATlPXhAzif////w84uPc=

Which decodes to (in hex ...

I may have lost track of this. But usually there a fixed number of days for comments and then a set day for a "ruling". What is the end date if any. That way I can just hibernate until then


The end date for reply comments was June 6, 2025. No date set for a ruling.

https://docs.fcc.gov/public ...

nickk wrote: Sat Aug 02, 2025 1:56 pm Found the code - the firmware gets the bsid from l1detail.

The bsid only appears in the L1_Detail if L1D_version is >= than 1. I'm gonna guess that there are plenty of transmitters sending a L1_Detail with L1D_version = 0 and no bsid.

The FCC has posted a document that seeks comment on the NAB proposal to sunset ATSC 1.0.

https://docs.fcc.gov/public/attachments/DA-25-314A1.pdf

From the document:

"Also, the Commission has received thousands of consumer comments objecting to broadcasters employing the use of Digital Rights ...