Posted on May 17, 2011 at 13:24I'm hoping to squeeze quite a bit out of the STM32, and am asking some advice to those who have interfaced with colour LCDs. No specifics yet, just trying to get a feel...
1. I plan to use the DMA controller for several peripherals (ADC, SPI, UARTS) as well as for transferring graphics from external NOR flash to the LCD controller (Epson S1D13517) using the FSMC. It's a 4.3'' 480x272, 24bpp screen, so I'm worried that the display will end up sluggish as the higher priority tasks take over. The GUI would mostly consist of updating gauges/bar graphs (10-20Hz) and some basic menu/settings pages. I've heard that the LCD demo that comes with the EVAL board shows that the performance is not very zippy, but I've also heard that this may be due to the slow LCD controller. Thoughts?
2. Although I've got a proposed set of DMA channels to use for the various peripherals and there's no channel conflicts as mapped so far, I'm worried still that the DMA controller will get clogged by the transfer from NOR flash to LCD controller, resulting in performance problems with the other high priority tasks (UART, ADC, SPI, etc). Should I be concerned?
3. To ensure good performance, I'm considering an LCD controller with a more enhanced graphics engine, something with BitBLT and such, so that at start up, I can load all the graphics/fonts to graphic memory, then send simple commands to copy/paste graphics from within the non-displayed area of graphic SDRAM to the displayed SDRAM. Eyeballing the Fujitsu Lime, but the datasheet is very poor and riddled with errors, and I've not been getting great support to clarify things. Anyone try this part out? Is this getting a bit excessive, as maybe the STM32 with an EPSON and NOR Flash could do the trick just fine?
