I spent a couple of days to fix this... The command DCR_CIRCLE_START doesn't work well when SPI it's working at over 10Mhz! Actually it's fixed for SPI_TRANSACTION compatible SPI libraries, should work ok for slow 8bit processors, really dunno DUE and ENERGIA based mcu's. The library and RA8875 works well till 14Mhz, over that SPI frequency it's start to create garbage on screen (text are unreadable) but I've noticed that circles result in garbage at 10/11Mhz, after several testings i find that DCR will exit the waitPoll too soon but was not enough, even DCR_CIRCLE_START distorts circles at high SPI speed, so I have to slow down DCR_CIRCLE_START and the DCR waitPoll then rise up speed again only when SPI speeds over 10Mhz are detected.
Using benchmark.ino sketch you can test if its' fixed for your MCU, if not please report me the SPI settings you using, the MCU and the IDE (plus the display). I have tested fix on the 800x480 but tomorrow I will test even on the 272x480 that uses slight different settings.
sumotoy
commented
9 years ago
I spent a couple of days to fix this... The command DCR_CIRCLE_START doesn't work well when SPI it's working at over 10Mhz! Actually it's fixed for SPI_TRANSACTION compatible SPI libraries, should work ok for slow 8bit processors, really dunno DUE and ENERGIA based mcu's. The library and RA8875 works well till 14Mhz, over that SPI frequency it's start to create garbage on screen (text are unreadable) but I've noticed that circles result in garbage at 10/11Mhz, after several testings i find that DCR will exit the waitPoll too soon but was not enough, even DCR_CIRCLE_START distorts circles at high SPI speed, so I have to slow down DCR_CIRCLE_START and the DCR waitPoll then rise up speed again only when SPI speeds over 10Mhz are detected. Using benchmark.ino sketch you can test if its' fixed for your MCU, if not please report me the SPI settings you using, the MCU and the IDE (plus the display). I have tested fix on the 800x480 but tomorrow I will test even on the 272x480 that uses slight different settings.