Monitor suggestions

neutrino · Post by **neutrino** » Tue Oct 25, 2022 4:39 am

On 10/25/2022 at 4:35 AM, TomXP411 said:

Maybe take the LSB of each color (one red, green, and blue line)

Probably the MSB?

On 10/25/2022 at 4:35 AM, TomXP411 said:

drive an I2C or SPI connection to the E-ink panel...

The I2C interface is likely too slow to drive e-ink displays now. The SPI is borderline fast enough.

Here's an example where the development of E-ink refresh rates and color is:

https://invidious.tiekoetter.com/watch?v=zjJ2-cdhwMQ

So I still think LVDS is most likely to the necessary type of link. But it may be that the VERA chip have a pin driver mode that can do LVDS right there.

Cyber · Post by **Cyber** » Tue Oct 25, 2022 6:08 am

On 5/27/2021 at 9:25 PM, TomXP411 said:

The only downside is that the native resolution is 1024x768, so you'll see scaling artifacts...

Currenly I have in mind 3 different LCD solutions for pixel accurate result without scaling artifacts:

1. Old 640x480 LCD. Perfect match. They are rare now, but they exist. I found one for myself.

2. Old or modern 1280x960 LCD. It scales perfectly to 640x480 using 2x2 monitor pixels for one VERA pixel. These also rare, but I saw new chinese models with such resolution.

3. Modern wide LCD with resolution ANYx1440 with 4:3 mode. In 4:3 mode VERA's output will occupy 1920x1440 pixels area, which scales perfectly to 640x480 using 3x3 monitor pixels for one VERA pixel.

TomXP411 · Post by **TomXP411** » Tue Oct 25, 2022 4:42 pm

On 10/24/2022 at 11:08 PM, Cyber said:

Modern wide LCD with resolution ANYx1440 with 4:3 mode.

Yup. There's a reason 1440 has become common. Not only is it halfway between 1920p and 2560p (aka 4K), but it's a good mode for scaling standard definition content.

TomXP411 · Post by **TomXP411** » Tue Oct 25, 2022 5:08 pm

On 10/24/2022 at 9:39 PM, neutrino said:

Probably the MSB?

I wrote correctly. I suggest you think about why removing the most significant bit in the DAC would be a bad idea before arguing the point.

Strider · Post by **Strider** » Tue Oct 25, 2022 7:18 pm

On 10/25/2022 at 1:08 AM, Cyber said:

2. Old or modern 1280x960 LCD. It scales perfectly to 640x480 using 2x2 monitor pixels for one VERA pixel. These also rare, but I saw new chinese models with such resolution.

3. Modern wide LCD with resolution ANYx1440 with 4:3 mode. In 4:3 mode VERA's output will occupy 1920x1440 pixels area, which scales perfectly to 640x480 using 3x3 monitor pixels for one VERA pixel.

This is the path I'm going down.

Also, some modern ASUS monitors have "Aspect Control", it allows you to switch between "full" and 4:3. I just tested it for the first time on the Z80-MBC2, and I really like it, looks so much better, but that's a text display. I think the monitor automatically adjusts to the input resolution, but I'm not 100% sure. If I don't have a monitor by the time I have an X16, I'll just use that feature and hope for the best in the meantime.

It's greyed out in the image below becasue the monitor is detecting the native 1080P input. If that changes, it allows you to switch to 4:3.

Johan Kårlin · Post by **Johan Kårlin** » Tue Oct 25, 2022 7:42 pm

I will try this! I don’t know if it will work well but at least it has VGA and 640x480 as native resolution.

TomXP411 · Post by **TomXP411** » Tue Oct 25, 2022 8:59 pm

On 10/25/2022 at 12:42 PM, Johan Kårlin said:

I will try this! I don’t know if it will work well but at least it has VGA and 640x480 as native resolution.

The one concern I have about these older panels is that the color fidelity isn't very good. I was using a security monitor with my U64 and, later, my The C64... and I stopped using it, because colors were all over the place. There's a huge difference in color quality between those old active-matrix LCDs and moder IPS panels.

Having said that... I love the look of this little monitor. ? ? That definitely looks like era-appropriate (even if it is about 15 years too late.)

Jazzhands · Post by **Jazzhands** » Tue Oct 25, 2022 11:31 pm

On 10/24/2022 at 7:16 PM, neutrino said:

Here's one color 13.3" E-ink at 800 US$ without taxes. But comes with "Purchase of E Ink Gallery related products requires signing a Non-disclosure agreement (NDA) & Software License (SLA) before shipment." ?

https://shopkits.eink.com/product/atelier-with-13-3˝-acep-display-ac133ut1/

At 11m:20s in this video, a USB connected to a PC e-ink tablet is demonstrated:

https://invidio.xamh.de/watch?v=KdrMjnYAap4&listen=false

I found this page the most interesting:

https://essentialscrap.com/eink/

Especially this datasheet at page 94:

https://essentialscrap.com/eink/S1D13521B01_Spec.pdf

So in essence you have to grab the digital screen data from the X16 and then transfer this to the memory of the display controller.

The X16 lacks any digital interface currently, but there are ways around it:

* Modify the RTL code loaded onto the VERA board and get digital output, at least the pixel clock.

* Piggy back on the VERA board oscillator (25 MHz) and feed the analog lines to an A/D. The A/D part is present in any LCD with an VGA input. The old screens usually drives the panel with digital LVDS..

* Make an expansion card that eavesdrop on the bus communication with the VERA passively, and then feed it to a VERA clone replicate the digital video data.

* Use a VGA-to-DVI adapter and then a FPGA to get from DVI to the actual digital RGB data.

You may want to make sure that a whole screen is grabbed in one sweep to avoid the shutter effect. Which means the memory (DRAM) to store this is needed.

The process is something like:

video source (X16) --> A/D --> memory --> e-ink controller with memory --> giant shift registers at the X and Y sides of the e-ink panel.

If you get the driver PCB from an old VGA-LCD then you can attach an FPGA+memory developer board to the LVDS output and most likely drive the E-ink gate/source (X/Y) shift registers directly.

Another approach is to use a PC with a video grabber and feed the output to an USB ready e-ink display. But this might possibly produce latency that is too high.

It all depends on your knowledge, equipment, time, budget etc.

That sounds quite complicated; certainly more than I know about hardware. Quel dommage.

neutrino · Post by **neutrino** » Wed Oct 26, 2022 12:25 am

On 10/25/2022 at 7:08 PM, TomXP411 said:

I wrote correctly. I suggest you think about why removing the most significant bit in the DAC would be a bad idea before arguing the point.

Sorry misread it as you wanted to use LSB part of the signal. ?

Cyber · Post by **Cyber** » Wed Oct 26, 2022 3:17 am

On 10/25/2022 at 10:42 PM, Johan Kårlin said:

I will try this! I don’t know if it will work well but at least it has VGA and 640x480 as native resolution.

I'm sure it will. I have exactly the same model.