Audioniek Images: download

[mrspeccy]

I have studied some things somewhat further and opened up the tuner modules in my possession. This revealed the following:

DVB-T(2): CXD2820R demodulator and TDA18212 tuner (new, tuner module number DNOQ44QCH106A, works on factory software, not on E2)

With the DVB-T2 module, there is a surprise. The driver is for the combination CDX2820R plus TDA18272, not the TDA18212 I found in my module. I looked three times with a magnifying glass, and I did not misread the number, as a 1 and a 7 can be mixed up easily in small print. The TDA18212 also exists and seems to be an earlier member of the NXP DVB-T2 compatible tuner chips of which the TDA18272, TDA18273 and the TDA18292 also are members. A quick hunt on the net did yield a brief product description, but no detailed data sheets.

Hi Audioniek,

impressive research. I can add that the DNOQ44QCH106A indeed works with E2, including your image; however, only DVB-T channels are found while channels in the DVB-T2 standard cannot be found. With the stock firmware, both types are found. I also made some tests. With your E2 firmware (the same holds for HDMU from 2017), I tried the following

cat /proc/bus/nim_sockets
NIM Socket 0:
Type: DVB-S2
Name: Availink AVL2108 DVB-S2
Frontend_Device: 0
NIM Socket 1:
Type: DVB-T
Name: Samsung CXD2820 DVB-T/T2
Frontend_Device: 1

That is, the tuner is recognized as DVB-T only, not DVB-T2, so it seems plausible that the channel search does not even attempt to tune in to channels in DVB-T2 format. On the positive side, it seems that the tda28278 driver (mind the 7) is compatible with the tda18218 to some extent, when it comes to DVB-T type channels.

I hacked the file driver/player2/linux/drivers/media/dvb/stm/dvb/e2_proc/e2_proc_info.c to force the type of the tuner to DVB-T2 (confirmed by nim_sockets). As a result, the Enigma2 menu mentioned DVB-T/T2 in the headline of the channel search while it previously only showed DVB-T there. Unfortunately, this time no channels were found at all - neither DVB-T nor DVB-T2 ones. Maybe the tuner crashed this time due to the wrong driver being used.

One thing I find curious: the build system includes the file driver/frontends/pace7241/tda18218.c (and related headers). However, I am not sure to what extent these files are useful.

[mrspeccy]

DVB-T2 works (kind of) with TDA28218/CDX2820!


The driver for the TDA28278 finally works on my box. However, it seems that I could not tune in to DVB-T2 channels before due to a timing issue. For example, in the source file cdx2820.c there are lines such as

msleep(30); /* fixme: think on this */

and similarly for the tda18272.c. I increased these pauses to 300 milliseconds and, after recompiling the related modules, I could receive DVB-T2 channels that I selected manually in E2. It is not stable yet, though; a full channel search sometimes misses some DVB-T2 channels. I will play around with these pauses/timeouts a bit. I also think that the issue with my DVB-S2 tuner that fails to select vertically polarized channels is a timing issue. This could explain that it works on Audioniek's hardware - mine is compatible but production tolerances for the hardware could make a difference. Will look into that later.

Finally, I found this URL: https://patchwork.kernel.org/patch/3757251/ It indicates that TDA28278 is a superset of TDA28218; as far as I understand it just includes some additional modulations that E2 may not use anyway.