aimatt

I figured it out. It needed 400kHz and address 0x3C. static const I2CConfig i2cconfig = { OPMODE_I2C, 400000, FAST_DUTY_CYCLE_2, };

Yes. The SPI output works for a different LCD (with uGFX) and the I2C is working with a barometer.

Yeah, no good. I'm giving up for now. O-Scope didn't really show anything on the SDA line, but then again, I'm not good with it. If you get some luck, let me know. I'm going to try to get U8glib working on it.

I just tried plugging SCK (PB13) into SCL and MOSI (PB15) to SDA, but no luck so far.

I have the SPI equivalent as well, it does look identical, but that has 6 pins instead of 4. I did get that one working successfully with some modifications to the SSD1306 code in the UGFX repo. Also, one of the buyers of this particular module did say they got it working with U8G_I2C_OPT_NO_ACK using U8Glib. Are you in the US? I can mail you one of mine if it comes down to that.

I bought one of these: http://www.aliexpress.com/item/Free-shi ... 91904.html and I can't get it to work on STM32L discovery I2C1 (LCD removed). The address as the jumper shows is 0x78 and there are only 4 lines. No reset pin. I can run an I2C scanner and pick up other devices (BMP180 and MS5611), but nothing else. I've tried with and without 4.7k and 2.2k pullups. After reading the comments I saw "works OK, used U8GLIB_SSD1306_128X64 u8g(U8G_I2C_OPT_DEV_0|U8G_I2C_OPT_NO_ACK|U8G_I2C_OPT_FAST) lib". I googled a bit and saw that this module may not be able to pull the line to set the acknowledge bit. Is there any way to shoe-horn this existing driver to work with it while allowing the slave to not sends ACKs, or do I have to implement bit-banging? Speaking of bit-banging-- is there a canonical implementation of software I2C for STM32 in the case that I do have to use it? Thanks a bunch!