Digole Digital Solution's Forum

Ralf Total Posts: 1 Since: 2014-Sep-22 From: Germany	Max SPI speed Posted at:2014-09-22 16:37:36
	Hello, please could you inform me about the max. SPI frequency for an OLED 1,8" True Color? It works fine with TWI (I2C with 400kHz) but doesn't do anything in SPI-mode (round about 1MHz). I have checked the SPI signals with an oscilloscope and these are ok. Anything to do in other ways than by I2C for initialisation? Thanks for your answer! Best regards, Ralf

Administrator

Total Posts:: 45
Since:: 2013-Dec-22
From:: Canada

RE:Max SPI speed

Posted at:2015-01-21 11:59:15

Hello Ralf,

The speed of communication is not critical, after receiving commands from communication port, the module will interpretate it and do according action, so, too fast to send command to module will cause the receive buffer overloaded and commands lost.

The hardware speed on SPI is very high, but after receiving each byte, the software need to pull the byte out and store it to the buffer, it also need time to do that, so, the 200K/S should be the highest speed.

gadgetmind Total Posts: 3 Since: 2014-Nov-03 From: United Kingdom	RE:Max SPI speed Posted at:2015-03-03 04:07:09
	Is there any way to poll the module using an extra pin to see when the buffer is getting full (or alternatively is completely empty) so I can drive it as fast as possible? Even a weak pull down on (say) MOSI when the buffer was 3/4 full would let me briefly switch MOSI to be an input to check buffer state.

Administrator Total Posts: 45 Since: 2013-Dec-22 From: Canada	RE:Max SPI speed Posted at:2015-03-03 07:56:12
	We currently didn't assign any out put pin to indicate the status of receiving buffer, but we can add this function for customized board for order quantity more than 49pcs.