Re: SSD1306 OLED driver

[Noralf Tronnes <notro@tronnes.org>]

Den 10.01.2015 22:07, skrev Ssagarr Patil:
> Hi Noralf,
>
>> Date: Sat, 10 Jan 2015 14:50:09 +0100
>> From: notro@tronnes.org
>> To: hugarsagar@outlook.com
>> CC: linux-fbdev@vger.kernel.org
>> Subject: Re: SSD1306 OLED driver
>>
>> Den 10.01.2015 13:34, skrev Ssagarr Patil:
>>> Hi Noralf,
>>>
>>>>>> I am now concerned if the driver was tested in first place ?
>>>>> No. I just submitted some good looking code that never ever got
>>>>> tested.
>>>>>
>>>>> More seriously, There's a few thing that comes to my mind:
>>>>> - Your controller doesn't behave the same way than the ones already
>>>>> supported.
>>>>> - You haven't posted your changes yet, so maybe you're not doing the
>>>>> transfers right
>>>>> - Your SPI controller is doing something weird
>>>>>
>>>>> What happens if you plug a logical analyzer on the bus?
>>>>>
>>>>> Maxime
>>>>>
>>>> Hi,
>>>>
>>>> The major difference between the SSD1306 SPI and I2C interfaces, is that
>>>> SPI uses a D/C pin to signal whether it's data or command coming in.
>>>> Looking at ssd1307fb, this Data/Command info is embedded as the first
>>>> byte in the i2c package/message.
>>>> Without looking up the datasheet, I would guess that this is the only
>>>> difference, the way the D/C bit is handled.
>>>> The rest of the package payload should be the same.
>>>> So:
>>>> dc=0, spi write command
>>>> dc=1, spi write data (optional)
>>>>
>>> I was working on ssd1306 itself.
>>>
>>>> Apart from that, I have SSD1306 SPI support in a project of mine:
>>>>
>>>> This is the part writing the framebuffer:
>>>> https://github.com/notro/fbtft/blob/master/fb_ssd1306.c#L173
>>>> This writes commands (for many controllers):
>>>> https://github.com/notro/fbtft/blob/master/fbtft-bus.c#L10
>>>> This is the SPI specific part:
>>>> https://github.com/notro/fbtft/blob/master/fbtft-io.c#L10
>>>> Project wiki: https://github.com/notro/fbtft/wiki
>>>>
>>> Thanks for the pointers that was really helpful.
>>>
>>> just a quick help the dc pin should be a gpio and be set as output pin
>>> to control D/C ?
>> Correct.
>>
> Thanks!
>
> Is there any sample app/library to draw/test  this driver?
I find it easy to just use the framebuffer console for simple testing: 
con2fbmap (or X windows)
I have also used Geert's fbtest.


Noralf.