<DarkNeutrino>
apritzel: So the guy from BIQU seems to be clueless about DRAM timings :( Any idea where we may be able to gather them from other then boot0 ?
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<apritzel>
DarkNeutrino: not really. I think how it usually works is that someone (probably AW itself?) generates those board specific delay timings once, and the board vendor just uses them
<apritzel>
and to be clear: it's not so much about the JEDEC timing parameters, but more about the board specific delay settings
<apritzel>
but the image provided by BIQU does work, doesn't it?
<apritzel>
I mean is it stable?
<apritzel>
If it's pure mainline, then this is using the OrangePi Zero2 settings, I think I saw them copying from that board a lot
<DarkNeutrino>
"Works"
<DarkNeutrino>
The board performance is suboptimal at best
<DarkNeutrino>
And lot of random issues that the community discovered
<apritzel>
do you reckon because of slow or badly configured DRAM? what's the DRAM frequency?
<DarkNeutrino>
apritzel: Exactly what im thinking. Let me check the datasheet for the chip
<apritzel>
DarkNeutrino: and can you do me favour and check what voltage RTC-LDO is, in the schematic? Our beloved "fixed custom" regulator? Would be either 1.8 or 3.3V
<apritzel>
DarkNeutrino: the datasheet for the chip won't help you much here
<DarkNeutrino>
apritzel: You mean the the frequency of it when the system is up ?
<apritzel>
the timings they use always differs from pure JEDEC timings. They seem to combine longer timings from higher speed bins, but run at a lower frequency
<DarkNeutrino>
Ah
<apritzel>
I meant CONFIG_DRAM_CLK in .config (or their defconfig)
<apritzel>
I tried to use better timings, but didn't achieve much on my H616 TV box
<apritzel>
(but I managed to improve DRAM performance on the F1C200s by ~20% with this method)
<apritzel>
but what we are actually after are the delay values, to compensate for board trace layout effects. We have seen different values in boot0 between the OpiZero2 and the TV boxes, for instance
<apritzel>
if the PCB layout and manufacturing process isn't the same as for the OPiZero2, they probably should use different values
<apritzel>
if you have a good indicator to judge the quality, you could experiment with those values, I guess
<DarkNeutrino>
Do you by any chance have axp313a datasheet in english ? The chinese version i have here is bit hard to read ;)
<apritzel>
I put it through Google Translate
<DarkNeutrino>
As for RTCLDO its passed to capacitor and resistor and to ground.
<apritzel>
that messed up the font a bit, but kept most of the layout, and provided a pretty decent translation
<DarkNeutrino>
No other references to it. Seems unused :|
<apritzel>
ah, even better, thanks
<apritzel>
I tried a proper implementation of this "fixed custom" regulator, but it's a bit more involved than I thought, and I need to pick broonie's brain on this
<apritzel>
(the regulator maintainer)
<DarkNeutrino>
Gotcha. I will try to pick the biqu guy brain. Tho chinese new year...
<apritzel>
right, that just started :-(
<DarkNeutrino>
Yea...
<DarkNeutrino>
BTW any recommendations for osciloscopes ? Used the ones we have at Uni but lets just say professor wasnt happy with me going overdrive on few boards
<DarkNeutrino>
Preferably where i dont have to sell some stuff to afford it as student xd
<apritzel>
I have no clue, cheap oscilloscopes seem to be on everyone's wish list
<apritzel>
if 10 MHz is enough, the very cheap ones reportedly do the job
<apritzel>
I guess it depends on what you want to check. For SPI, I2C, and GPIO it's probably fine to go with a cheap one, but already (e)MMC probably requires more like 100MHz bandwidth
<apritzel>
that moves the hardcoded values (from the OPiZero2) to Kconfig variables, so you can set them in *_defconfig
<DarkNeutrino>
Oh fantastic
<apritzel>
check the changes to the two *_defconfigs in the series to get an idea
<DarkNeutrino>
Already did :)
<DarkNeutrino>
Quick question. Did anyone experiment with HDMI on h616 ? I tried it few weeks ago. The connector was recognized and it knew it was plugged in. But didnt read any EDID data and outputed lovely purple color on display.
<DarkNeutrino>
Need to get some way of controlling this board. UART aint cutting it ;) And ofc BIQU decided they are too cheap for Gigabit ethernet so the internal 100Mbit it is and we dont have driver for that.