2013-10-13 10:50 AM
Hi :)
As usual 'Murphy law' i get little problem .... I have connect 3 different USB Stick on 3 Different F429 Disco Board though the microSD connector with no results. I then tried with a USB connector directly connected to the USB dedicated pins with the same no results :( Is it something special to do to made it work ?? From the docs i doesn't see anything special to do for the micro usb port , i have think it will be functional directly with the provided demo ... I formatted them in fat16 and fat32 for be sure and they are 1,2 and 4Gb. Cheers. #discovery #stm32f429 #lcd-tft2013-10-15 09:40 AM
Hi ,
Good point , i will have to look at frequency , i don't know if it is possible to made OTG work at less than 48Mhz , but if we put 8 in PLL_Q then we get 45Mhz ... Something to try i think :) Cheers.2013-10-15 10:01 AM
Or retreat to 168 MHz?
The 180 MHz conundrum has been troubling me for a while. We have 3 PLL's now with 3 taps, and the one used for USB is tied to the CPU, and no alternatives. There are a lot of frustrating trade-offs.2013-10-15 10:34 AM
''Or retreat to 168 MHz?''
Hmmm ... NO :) Tomorow after work i try PLL_N at 384 + PLL_Q at 8 .. This give 48Mhz for USB and the STM is then over-clocked at 192Mhz ... On my old Disco board i tried overcloking at more than 200Mhz without problem. But now with SDRAM Timing i have to check :) Cheers. PS : ST have probably think ... ''Run those little beast at 192Mhz'' ... but made a typo and write 180Mhz in the Docs ... he he2013-10-15 10:55 AM
I can not wait tomorow :)
I just made the change in the demo and now ... it work :) Thanx Clive to pointed me on that frequency info :) What i do in system_stm32f4xx.c change : #define PLL_N 360 in : #define PLL_N 384 /#define PLL_Q 7 in: #define PLL_Q 8 and don't forget : uint32_t SystemCoreClock = 180000000; in: uint32_t SystemCoreClock = 192000000; Well , apparently the LCD + SDRAM are still working correctly , now they are probably timer that are no more accurate if they are configured for 180Mhz... Cheers. PS : the other demo : ''LTDC_AnimatedPictureFromUSB'' with same parameter work too ;)2013-10-15 12:06 PM
Yes, 192 MHz would have been a better choice, got to think there is a critical path in there somewhere, would be nice to chat with an ST design engineer to understand where the limits are.
Something like this will make your life easier uint32_t SystemCoreClock = (((HSE_VALUE / PLL_M )* PLL_N) / PLL_P);2013-10-15 12:32 PM
I like when you start Math :)
Tomorrow i copy/paste this in my source ... here in France is bed time ;) And about max frequency , more than 200Mhz with stm32f407 Disco was not a problem. Here we just up 12Mhz. I start my VGA demo that is very intensive with SDRAM etc and let it run for the night. If it still work when i wake up then it's good for me ;) Cheers.2013-10-15 02:47 PM
Hi guys !
I come back with my USB device problem.So I put the frequency at 168 MHz, I made a small test program with the board configured in USB device in HID class -> work perfectly ! It is recognize by the PC. I think there is no HW problem.But the same basis SW but configured in USB device CDC -> fail !The device is not well recognized by the PC.On the my STM32F4 board discovery this was working well... Bug in the ST SW to handle CDC device with HS core used in FS ? Is the HS core (HW) is able to handle CDC class in FS mode ?2013-10-16 09:41 AM
Hi ,
My board run since yesterday at 192Mhz without problem :) @chicher : what is your frequency defined for the HSE_VALUE ? in ....\CMSIS\Device\ST\STM32F4xx\Include\stm32f4xx.h The original version from the file is every-time 25000000 !! don't forget to change that for 8000000 , we don't have 25Mhz crystal on the board :) This thing made me mad when i started with the stm cpu ... he he Cheers.2013-10-16 09:42 AM
Wish this had been on another thread as it's a bit Off-Topic from the USB MSC Hosting.
I've poked around a little with the VCP driver, porting it to the STM32F429I-DISCO USB library, have it recognized but getting an ''This device cannot start. (Code 10)'' indicator.2013-10-16 11:31 AM
Ok, suppressed the Code 10