mrwaug / u8glib

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NHD-27-12864-OLED displaying 'snow' #294

Closed GoogleCodeExporter closed 8 years ago

GoogleCodeExporter commented 8 years ago
Around 9 out of 10 times, when starting the display, instead of showing the 
image, it just displays 'snow'. the 10th time the display works correctly.

The problem occurs on different displays, both the same type NHD-27-12864-OLED. 

I tried both reset methods, using the RC combination (1K and 100nF) and having 
u8g handle the reset using the following constructor:

 u8g_InitSPI(&u8g, & u8g_dev_ssd1325_nhd27oled_2x_bw_hw_spi, PN(1, 5), PN(1, 3), PN(1, 2), PN(1, 1), PN(4,5));  

The software runs on an blank atmega328

Any suggestions on how to solve this problem?

Original issue reported on code.google.com by coolyroe...@gmail.com on 3 Nov 2014 at 6:57

GoogleCodeExporter commented 8 years ago
i found that when the display show 'snow', manually pulling the reset low, and 
then resetting the MCU, fixes the problem for the next startup.

after unplugging the device and plugging back in, the problem starts occurring 
again. 

Original comment by coolyroe...@gmail.com on 3 Nov 2014 at 7:12

GoogleCodeExporter commented 8 years ago
Well.. a workaorund could be a second reset.
Use
u8g_Begin(&u8g);
to force another reset of the display.
If you see some snow, then the startup data has been transmitted successfully.

Original comment by olikr...@gmail.com on 3 Nov 2014 at 7:25

GoogleCodeExporter commented 8 years ago
no further response...

Original comment by olikr...@gmail.com on 13 Dec 2014 at 5:28