I may not have answered your question, the dts is bbb-4dcape70t On Tuesday, November 3, 2020 at 3:36:42 PM UTC-6 amf wrote:
> Hi Mark, > I do custom builds with yocto, the meta data is from jumpnowtek. kernel > version linux-stable_5.7 > In addition to the info that RCN provided, I added the pin mux stuff to > define all the gpio pins. > > looked at the driver for the R/W issue, seems they do not set the R/W bit, > they do set the RS bit, so maybe just need to add the same for the R/W bit. > > amf > > > > On Tuesday, November 3, 2020 at 1:29:28 PM UTC-6 Mark A. Yoder wrote: > >> Thanks to all for following up on this. >> >> amf: What device tree are you using? >> >> --Mark >> >> On Tuesday, November 3, 2020 at 10:26:52 AM UTC-5 amf wrote: >> >>> Just wanting to follow up on this. The LCD display is working, just had >>> to remove the R/W parameter from the dts and tie the LCD R/W to ground. The >>> driver does not seem to support reading from the display, so no harm in >>> doing it this way. >>> >>> amf >>> >>> On Monday, November 2, 2020 at 6:56:25 PM UTC-6 amf wrote: >>> >>>> Hi Mark >>>> Seen RCN's response below. I have several of the *hd44780 LCD displays >>>> also, *spent the weekend trying to get it to work with the info RCN >>>> provided. Seems the R/W line is always high, thus all the data signals are >>>> distorted. If I pull the R/W line low, then the data signals are ok, but >>>> nothing is written to the display. I know the displays are good, I wrote a >>>> uart-to-parallel with an atmel chip several years ago. if you have success >>>> with the Linux driver, I would like to know. >>>> amf >>>> >>>> On Thursday, October 29, 2020 at 1:39:54 PM UTC-5 Mark A. Yoder wrote: >>>> >>>>> I've just recently discovered I have access to lots of 16x2 LCD >>>>> displays. >>>>> >>>>> I see there are many examples of interfacing it to a Linux machine, >>>>> but most are via user space. I'm looking for kernel space examples. >>>>> *modinfo >>>>> hd44780* shows a driver is there, but how do I use it. >>>>> >>>>> Is there a device tree for the hd44780 for a parallel interface? >>>>> >>>>> --Mark >>>>> >>>> -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/4ee6f3ed-d7e1-42ec-a3bd-d882e445b290n%40googlegroups.com.