RA8875 and Encoder counter

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max_yoshida
 
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RA8875 and Encoder counter

Post by max_yoshida »

Hi there, I have a project that shall be done by Arduino MEGA2560, mainly it includes knowing a DC motor position via encoder feedback, and a big colored touch screen to show data. So I was thinking about using TFT product 1596 with driver product 1590 to achieve this, beside a hardware Encoder counter to take off load from CPU and make sure we don't miss pulses.

My questions:
1) Are products 1596 and 1590 compatible? I think they are, Just making sure before I order!
2) What pins does 1590 need to be connected to in Arduino MEGA2560? I read example sketch but can't figure out pins for touch coordinates (X+, X-, Y+, Y-), LITE and WAIT, beside that do we need to connect 3V0 to 3.0V source or connecting VIN to 5V is enough?
3) How to read touch coordinates from 1590? I think INT value changes when touch occur, is there a sketch for this? How to read X and Y values? (No need to show exact sketch, I can program by myself if I get exact idea on interfacing)
4) If I show text on TFT screen for example, then show another text on same position without clearing, will both texts appear above each other? (Knowing this will be useful in writing code to update screen and knowing load on CPU)
5) Do you have an Encoder counter hardware shield? I searched website but couldn't find one!
6) When 1596 is connected with 1590 and power is applied, also backlight LED brightness is 100%, what is maximum current consumption for 1590 and 1596 together?

Thank you so much!

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adafruit_support_rick
 
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Re: RA8875 and Encoder counter

Post by adafruit_support_rick »

max_yoshida wrote:1) Are products 1596 and 1590 compatible? I think they are, Just making sure before I order!
Yes!
max_yoshida wrote:2) What pins does 1590 need to be connected to in Arduino MEGA2560? I read example sketch but can't figure out pins for touch coordinates (X+, X-, Y+, Y-), LITE and WAIT, beside that do we need to connect 3V0 to 3.0V source or connecting VIN to 5V is enough?
You don't connect the touch - those are broken out in case you want to use a separate touch controller, like the STMPE610. The RA8875 handle touch events over SPI. You also don't need to connect WAIT or LITE.
max_yoshida wrote:3) How to read touch coordinates from 1590? I think INT value changes when touch occur, is there a sketch for this? How to read X and Y values? (No need to show exact sketch, I can program by myself if I get exact idea on interfacing)
INT will tell you when a touch occurs. Otherwise, you can poll for touches. The buildtest example demonstrates touch polling.
max_yoshida wrote:4) If I show text on TFT screen for example, then show another text on same position without clearing, will both texts appear above each other? (Knowing this will be useful in writing code to update screen and knowing load on CPU)
If you use transparent mode text, then both texts will appear. If you use text color mode, then the background will always draw over the previous text. The textmode example demonstrates the various text modes.
max_yoshida wrote:5) Do you have an Encoder counter hardware shield? I searched website but couldn't find one!
No.
max_yoshida wrote:6) When 1596 is connected with 1590 and power is applied, also backlight LED brightness is 100%, what is maximum current consumption for 1590 and 1596 together?
About 250mA

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max_yoshida
 
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Re: RA8875 and Encoder counter

Post by max_yoshida »

adafruit_support_rick wrote: You don't connect the touch - those are broken out in case you want to use a separate touch controller, like the STMPE610. The RA8875 handle touch events over SPI. You also don't need to connect WAIT or LITE.
Thanks, I saw product 1571, but I still need to ask, do we get x and y coordinates input from driver? The pins you said they are broken?? About output I see 3 methods to connect pins, which one is recommended with tft driver? What to do with other pins that are not told to connect them in sketch? Ignore them?
Also you didnt tell me yet, do we need to connect 3V source or 5V is enough alone for both driver and touch driver?
Thank you so much for useful information!

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adafruit_support_rick
 
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Re: RA8875 and Encoder counter

Post by adafruit_support_rick »

The pins aren't "broken". "Broken out" is English idiom meaning that the pins are provided for your use.
max_yoshida wrote:About output I see 3 methods to connect pins, which one is recommended with tft driver?
Not sure I understand the question. What three methods? You connect SCLK, MISO, MOSI, CS, RST, and INT. Ignore all other pins.

You can connect either 3.3V or 5V to Vin.

Touch coordinates come from the RA8875 driver, as demonstrated by the buildtest example. There is no separate touch driver.

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darla
 
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Re: RA8875 and Encoder counter

Post by darla »

thank you for sharing ...


darla

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max_yoshida
 
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Re: RA8875 and Encoder counter

Post by max_yoshida »

Thank you so much adafruit_support_rick, you really helped me a lot and I appreciate it! Now I do understand that I only need product 1596 and 1590 to show anything at screen and detect touches also, beside that, this is done via SPI and no need to connect (X-, X+, Y- and Y+) pins to anything, examples show them all! And about power, eihter 3V or 5V will work and no need to connect both together, also since current consumption is about 250mA, it is recommended to connect VIN to external supply not Arduino, just to take off load from Ardino regulator, I will choose a 5V/1A charger and connect output to both screen and arduino.

Saying this since am hoping somebody will look at this post and gain required information he/she didn't know before!

Thanks again!

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adafruit_support_rick
 
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Re: RA8875 and Encoder counter

Post by adafruit_support_rick »

You're welcome!

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