LDR Pre MkII - LDR volume control and I/O switching

Hi zdr

I procured and replaced the LDRs and also the mosfets and still I am unable to finish the calibration process. I could set the bias and measure everything but unable to go beyond step 2 in the calibration. So errors like earlier but any idea how long does it take for the calibration to finish successfully and how many steps are actually part of the calibration process? The old design boards used to take around 10 mins so do let me know.

thanks
 
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Hi zdr

I procured and replaced the LDRs and also the mosfets and still I am unable to finish the calibration process. I could set the bias and measure everything but unable to go beyond step 2 in the calibration. So errors like earlier but any idea how long does it take for the calibration to finish successfully and how many steps are actually part of the calibration process? The old design boards used to take around 10 mins so do let me know.

thanks

If you are having errors during boot time, they MUST NOT be ignored. Nothing will work until they are cleared. I provided a way around them simply to allow users to enter various DC states for easier troubleshooting.
 
R4 - remove
R3, R5, R7 - OR (short with blob of solder)
DC - connect to VCC with 10K resistor (pullup)
RES - connect to VCC with 10K resistor (pullup) and connect to RST on Arduino.

No need for connection to reset pin on Arduino anymore if you do this mod:

R4 - remove
R3, R5, R7 - 0R (short with blob of solder)
DC - connect to VCC with 10K resistor (pullup)
RES - connect to VCC with 10K resistor (pullup)
RES - connect to GND with 10uF cap (keeps RES low during display power up)

With this mod, display is now direct drop-in replacement for the one from wide.hk.
 
IMG_5655.jpg
 
I could make my LDR board to work as expected. Now when I power up it boots and stands with 3 dots and I need to press the play button for 3 seconds to start the board. Can I not power the rotary encoder? Will this work only with the remote as I thought we can use the rotary encoder long press also might work. Any guidance.

thanks
 
Hello zdr,
Thank you for making this new Oled screen work :). I had problems with the Oled 2.42 screen SSD1306 from Wide :( who is out of order and as it is difficult to find this screen, I want to know if the screen you propose for your LDR PRE can work with Arduino based LDR volume and source selection controller without modifying your program VxD_OLED_4X2s? You put two photos
post #177 and #188 with the hardware changes, what is the good photo?
The white wire must be connected on arduino reset? thank you very much for your help.
 
Yes. Bypass them and use a home theatre amplifier as the volume/pre amp. That way you use the ldrs to listen to quality music. But when I want to use surround sound and watch a movie, you bypass the ldr attenuation and use the HT amp as the receiver/decoder. I have this bypass function on a previous ldr build and it works very well.