FTDI Community
General Category => General Discussion => Topic started by: armadafg on May 15, 2018, 11:02:13 PM
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in English:
Hello FTDI :) ,
I am a user of the excellent gamduino2 and its ft810 and I also use the ft811 with teensy3.6. I love your chips and I'm not the only one. But we face limitations that its problematic for my projects for example the limitation of the number of instrution by images (about 2000) or 1Mbits of VRAM, I would like to be able to have the possibility of l'etante by external VRAM . I would like to know if a ft82x was in preparation or possible?
En francais (l'original)
Bonjour FTDI :) ,
Je suis un utilisateur de l'excellent gamduino2 et de son ft810 et j'utilise egalement le ft811 avec des teensy3.6. J'aime beaucoup vos chip et je suis pas le seule. Mais nous faisons face a des limitation qui son problematique pour mes projet par exemple la limitation du nombres d'instrution par images (environ 2000) ou des 1Mbits de VRAM, j'aimerait bocoup avoir la possibiliter de l'etante par de la VRAM externe. J'aimerait savoire si un ft82x etait en preparation ou envisagable ?
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Hello,
Our upcoming BT815/6 series of EVE ICs also include 1MByte of internal graphics RAM. However these new ICs include support for external flash memory which can be used to store/offload graphics elements such as images, custom fonts and widgets from the integrated RAM.
You can find out more about the BT815/6 at the following page:
http://brtchip.com/bt81x/ (http://brtchip.com/bt81x/)
Best Regards,
FTDI Community
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eng:
brtchip is FTDI ? My biggest problem comes from the 2000 instruction and nothing tells me that the BT81x will solve this problem. And stay to see what the VRAM bus will give you
fra:
brtchip c'est FTDI ? Mon plus gros probleme vient des 2000 instruction et rien me dit que le BT81x resoudra ce probleme. Et reste à voire ce que vas donner le bus de VRAM
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Hello,
The new series of BT81x ICs will have the same amount of VRAM as its predecessors.
We have some examples of what is possible with this at the following:
http://www.ftdichip.com/Support/SoftwareExamples/FT800_Projects.htm (http://www.ftdichip.com/Support/SoftwareExamples/FT800_Projects.htm)
Best Regards,
FTDI Community
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Adding to this, the 2000 entries in the display list is not the only limitation I am wondering about.
I did some profiling and found that VERTEX2F is a huge bottleneck because of the odd positions the X corrdinate has to be shifted in.
This is a major pain when working with calculated coordinates.
Especially with 8 Bit controllers which kind of are the designated target for the EVE series.
But this also has to have some impact on 32 bit controllers.
I would apreciate a command that at the cost of one bit resolution has the X coordinate not shifted.
Or heck, make that two bits shorter and 1 pixel resolution by default, that would be a range of +/- 4096 to set.
I also would not mind patching VERTEX2F for a faster operation of the FT81x but FTDI/Bridgetek would need to supply such a patch as the inner workings of the FT8xx are only partly explained.
What also is very slow is PNG support in FT81x.
I clocked a simple test picture with 3867 bytes to take 53ms for processing after sending the data.
While a JPG with 3903 only needed 480µs to process.
That means JPG is 110 faster than PNG.
Maybe this is the reason why PNG is missing from the table at http://brtchip.com/bt81x/ ?
Also I am wondering why the BT815/816 datasheet has not been updated so far with a release due next month.
The draft version really has nothing new so far, at least not in any detail.
Even more I am wondering why the FT81x programmers guide is not getting any updates despite the numerous bugs it contains and of which I reported some over a year ago.
And am I the only one wondering why the next device is named BT816 instead of BT814? :-)
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Hello
Thanks for you suggestions regarding the API functions, I will certainly pass these along to the development team.
The datasheet and the Programmers Guide are currently in an update and review cycle. Once this has been finalised they will be released to the public.
Best Regards,
FTDI Community
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First and off-topic, do we eventually earn the right to post here without approval of a moderator?
And it is the 2nd of June already and http://brtchip.com/bt81x/ has not been updated yet.
Unbelieveable, I demand an update now! :-)
No, actually I do not but I would apreciate more information and an updated programmers guide.
Btw. the "FT81x Series Programmers Guide" link on that page is actually pointing to the FT81x datasheet.
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Hello Rudolph,
Unfortunately Moderator approval is required for all posts due to our internal security policy.
I believe the updated Programmers Guide will be available when the IC is officially released in the upcoming months.
Thank you for pointing out the incorrect link, I will let the web team know to update this.
Best Regards,
FTDI Community
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Hell,
So if I understand the BT 815/6 is a FT81x with 72mhz max instead of 60Mhz, the external memory, ASTC and still 2000 instruction max right?
How much flash memory can we add to the maximum?
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Hello,
Yes, the BT815/6 supports QSPI NOR flash chips with I believe a capacity of up to 265 MiB.
Best Regards,
FTDI Community
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Cypress has 1GBit NOR QSPI devices and Micron has 2GBit devices, Gigadevices has 512MBit.
SPI NAND however would be upto 8GBit.
If availability is the limiting factor: :-)
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Hello,
Do you think that there is a method of exceeding the 2000 instruction by image with the FT81x and the BT81x?
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Hello,
As previously mentioned the BT815/6 (like the previous FT80x) includes 1MByte of internal graphics RAM, which will limit you to ~2000 instructions. However these new ICs include support for external flash memory which can be used to store/offload graphics elements such as images. Alternately you could store images on an SD card if your MCU has support for this.
Best Regards,
FTDI Community
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I'm sorry but I understand that the BT81x has 1M Vram in addition to the external ram but the number of instruction and the amount of RAM do not have anything to do.
The FT800 has only 256k and the FT810 has 1024k that said there is the same limit of instructions.
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Hello,
Sorry I ment to say "As previously mentioned the BT815/6 (like the previous FT80x) includes 1MByte of internal graphics RAM, and the same sized RAM_DL which will limit you to ~2000 instructions". I.e. that RAM_DL has not increased so the limit on instructions is the same.
Best Regards,
FTDI Community
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Hi,
So why for example the gameduino2 that uses the ft800 with 256k and the gameduino3 that uses the ft810 with 1M its both block has 2048 commands ?
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All FT8xx so far have 8k of memory for the display-list, that is 2048 32-bit words.
Expanding this to 64k would be nice on first glance but then everything still would need to be executed for every single frame.
So at the same time the chip would need to be much faster.
This reminds me of a different "issue".
The divider for the clock only works well for small displays.
800x480 is configured to 928 h-cycles und 525 v-cycles, that are 487200 clock-cycles.
A typical value for the divider would be REG_PCLK = 2 which means that a FT81x uses 30 MHz.
In return these settings result in about 61 frames per second, nice.
Now I have this 1024x600 TFT from Glyn.
For some reason (I suspect a flaw in the design on Glyns side) these can not be used with the full clock of 60MHz.
As these are configured to 1100x720 this would result in 75 frames per second anyways.
The recommended value is 20MHz and therefore 25 fps and they work well with 30MHz which results in 37 FPS.
The issue I have there is that the divider does not allow for fractional values, so I could not configure it to
use 45MHz for example which would result in 56 fps.
Now the upcoming BT81x uses 72MHz.
That is nice, so the 1024x600 panel could be used with 45 fps.
The 800x480 panel at REG_PCLK = 2 would run with 73 fps so we need to make that REG_PCLK = 3.
But then it would be clocked with 24MHz and "only" 49 fps.
If for whatever reason you would need to fine-tune the frame-rate you simply could not do that.
One could come up with the idea to manipulate the base-clock but the datasheet does not give a frequency range, the only allowable frequency is 12MHz.
The PLL could be changed to multiply by 2...5 (6 with BT81x).
At higher resolutions this would even become more of an issue.
Do I want higher resolutions or do I need them?
No, not really, I would be fine with 4 pixels per mm for HMI. Or make that 8 pixels per mm.
The typical 800x480 7" has 11 pixels per mm.
But what I need are bigger displays and there close to none 800x480 or 800x600 panels bigger than 7" out there.
And the bigger panels do not only have higher resolutions, they also typically do not have a RGB interface anymore but LVDS instead.
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Thank you for your reply Rudolph :) ,
So you want to say that if we increase the memory for the display-list to 16K for example there would be 30 img / s instead of 60 and it does not vary according to the instruction in question or it depent of what its instructions ? (here for 480 * 800)
For my part I will not have the benefit of having more pixel, 5" and 480 * 800 are fine.
Creating another chips that will be managed more resolutions why not but it is not my priority.
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>So you want to say that if we increase the memory for the display-list to 16K for example there would be 30 img / s instead of 60
No, I am saying that if the display-list would be increased the chip also would need to be made faster.
At least fast enough to handle 60 FPS for the max designated resolution which now is 800x600.
Only the first three lines of my post refer to the limited display-list, the rest has nothing to do with it. :-)
And maybe it even currently is fast enough to handle 16k for example, from a few observations I can only tell that it is pretty fast already,
but not how busy it really is from frame to frame.
I was merely pointing out that expanding the display-list memory looks like an easy thing to do from the outside, for example the gfx-memory could be reduced at the same time so the overall memory stays the same.
But it is more complicated then that and there is not much information around about how the FT8xx do function internally.
Thinking about it I wonder for example how the lists really work.
The display is written out line by line with no frame-buffer.
The objects however are all over the display-list. You can display a picture at the start of the list on top of the screen, lots of things in the next instructions and then a text to be printed across that picture at the end of the list.
So one way to do it would be to process the whole display-list for every single pixel - which I find a bit unlikely.
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I really hope the next br82x will have more than 16k of memory.
512k. The absolut dream ;) 8) :o ;D
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Hi,
While waiting for the next chip to handle more than 2048 instructions, but do you know if hotmcu is expected to use the BR 815/6?
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I would also like to know when the bt82x will be available.
On your site it is indicated June 2018 but I do not see it anywhere
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Hello,
The BT81X should be available by the end of the year.
Best Regards,
FTDI Community
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I do not know about Hotmcu and I am not sure if I really want to anymore.
But it looks like Matrix Orbital has plans for BT815/BT816 modules: https://www.matrixorbital.com/ftdi-eve/eve-bt815
>The BT81X should be available by the end of the year.
Hmm, not so nice.
Okay, what about updating the datasheet and perhaps the programming manual in advance, perhaps with a fat PRELIMINARY watermark across all pages?
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Yes maybe but the problem is that Hotmcu's screens are much cheaper
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That is the problem for me Hotmcu's screens are much cheaper and not so much less expensive.
And the BT815/BT816 are in full release now. :-)
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when i say "much cheaper " i mean "less expensive". (translation problem fr -> en, sorry)
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I was aware of what you mean but I wanted to point out that I have an issue with the quality they deliver.
Sure, these are good value for the money, not bad products, but I want more value.
Now that the datasheet for the BT81x is released, these support up to 2GBit of QSPI NOR flash. :-)
And they can play animations and videos directly from external flash plus using fonts and images.
Some interesting features include UTF font support, printf style text output, using strings from memory.
I only have to get a BT815 module now.... :-)
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2...G...B :-O
Unbelievable
I hope Hotmcu you have one with the 2Gb because for my project I find that their quality is sufficient
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I just learned that 2Gbit is rather unlikely since, at least by now, you will not find these in SOIC-8 or WDSON-8 packages but BGA packages.
Well, 64MBit already would be a huge step up, SOIC-8 would mean 256MBit max and WDSON-8 would mean 512MBit max.
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Anyway, even if there were only 256m it would still 256 times more than the ft81x
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I would like to know if it is possible to exceed 60 i / ps with the FT81x or bt81x?
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Hello
Basically the refresh rate depends on which Display you are using, the PCLK that this display can support, and its size. Multiplying the HCYCLE and VCYCLE values will give you the total number of Pixels to be rendered, dividing this number by PCLK will give you the theoretical refresh rate for the display.
Best Regards,
FTDI Community
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thank you for your reply.
So if I understood well with this screen : http://www.haoyuelectronics.com/Attachment/HY5-LCD-HD/KD50G21-40NT-A1.pdf
I do 1 / ((800 * 480) / 50000000).
which makes 130 i / ps ?
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Hello,
If we take the example from the following WQVGA settings:
// WQVGA display parameters
lcdWidth = 800; // Active width of LCD display
lcdHeight = 480; // Active height of LCD display
lcdHcycle = 928; // Total number of clocks per line
lcdHoffset = 88; // Start of active line
lcdHsync0 = 0; // Start of horizontal sync pulse
lcdHsync1 = 48; // End of horizontal sync pulse
lcdVcycle = 525; // Total number of lines per screen
lcdVoffset = 32; // Start of active screen
lcdVsync0 = 0; // Start of vertical sync pulse
lcdVsync1 = 3; // End of vertical sync pulse
lcdPclk = 2; // Pixel Clock
lcdSwizzle = 0; // Define RGB output pins
lcdPclkpol = 1; // Define active edge of PCLK
HCYCLE = 928
VCYCLE = 525
VCYCLE * HCYCLE = 487,200
Note: REG_PCLK is using the value 2 which will divide the clock down to 30Mhz.
Result = 30,000,000/487,200 = ~ 61
The intention in this example is to get the refresh rate at or near 60 fps, but if your display can support higher PCLKs then a higher refresh rate should be possible.
Best Regards,
FTDI Community
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ok i understand better.
For this screen in question the frequnce max is 50mhz, so the best conbinaison with the ft811 or bt81x is 30Mhz ?
And for the bt81x it is necessary to find a screen with 72mhz max to use all this capacity? That's right ?
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Hello,
In general most displays target around a 60 fps refresh rate, as such settings are chosen to achieve this. In the previous example the clock was divide down to 30Mhz as this number combined with the HCYCLE and VCYCLE values got use very close to this desired number (60). It is normal practice to divide PCLK by 2 or more to achieve the desired frequency which best fits the display being used.
It is not the intended use of EVE to run at 'full tilt' with a display that can match the overall system clock of the IC.
Best Regards,
FTDI Community
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Hi,
If the bt82x is designed for the 60ips in which case the 72Mhz or the 60Mhz is used?
Moreover with the screens of Hotmcu I manage to use the 60Mhz but only if there is not too much elemnt to display on the screen whereas it is indicated in this documentation that it can not exceed the 50Mhz.
Do you know a screen capable of exploiting the 72Mhz?
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Hello,
The BT81x is capable of implementing a 72Mhz or 60Mhz clock, this is the main clock in the IC. It is the DISPLAYS that are usually designed to operate at 60fps, not the IC. Typically a much lower PCLK is used to drive a display within its design spec.
Sounds like you pushed the display past its spec. and it stopped functioning correctly.
I am unaware of any displays currently which will make use of an 72Mhz PLCK, again lower PLCKs are usually used as displays are targeted to run at 60fps.
Best Regards,
FTDI Community
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The screen still works correctly, it is only when there is too much element to display that the image is deformed. If not, it will function properly at about 110ip / s.
If ever a person passing through this forum knows a screen with this ability please share it. ;D