Search found 5949 matches

by RogerClark
Tue Jun 27, 2017 1:24 am
Forum: Linux
Topic: Install STM32duino on Raspbian?
Replies: 1
Views: 22

Re: Install STM32duino on Raspbian?

There isn't support for compiling on the RPi at the moment. However someone has submitted a PR with the files to do this. See https://github.com/rogerclarkmelbourne/Arduino_STM32/pull/283 No one has had time to test whether this PR is OK, hence its not been included yet. And after inclusion, it woul...
by RogerClark
Tue Jun 27, 2017 1:20 am
Forum: General discussion
Topic: convert PORT to int
Replies: 3
Views: 23

Re: convert PORT to int

Pins are just an index into a PIN_MAP array

I think you could use a single byte, but as the MCU is natively 32 bits, is usually best just to use int for integers unless you need to do some specific bit shifting or masking that requires an 8 bit value

So... use

int
by RogerClark
Mon Jun 26, 2017 10:08 pm
Forum: General discussion
Topic: convert PORT to int
Replies: 3
Views: 23

Re: convert PORT to int

If you want to read an entire port ( 16 bits), at the moment you will need to use the built in reference to the port struct ( device) and its input reguster.

I am sure other people have posted some snippets of code. try googling for fast GPIO access or port access
by RogerClark
Mon Jun 26, 2017 10:04 pm
Forum: General discussion
Topic: Should we still use optimisation level -Os (Small)
Replies: 15
Views: 192

Re: Should we still use optimisation level -Os (Small)

zmemw16 wrote:
Mon Jun 26, 2017 10:29 am
can't we just default it to -Os ? as now in effect, let user then change it if reqd.
srp
Yes.

It could be done
by RogerClark
Mon Jun 26, 2017 10:03 pm
Forum: Projects
Topic: OV7670, Generic STM32F103RC and ILI9341 display
Replies: 84
Views: 6493

Re: OV7670, Generic STM32F103RC and ILI9341 display

@indrekluuk Thanks for posting. Perhaps I should have put a link to this thread in my reply to your youtube post. i am using the ILI9341 display which is QVGA, and also the byte order of the data is reversed from what the camera sends I do a bit if a hack, by simply transferring the entire pixel buf...
by RogerClark
Mon Jun 26, 2017 9:46 pm
Forum: General discussion
Topic: SD card on ILI9341 display board??
Replies: 17
Views: 218

Re: SD card on ILI9341 display board??

SDcard's SPI signal path resistors - they usually put there 1k resistors to avoid excessive currents when connecting Sdcard to 5V logic (poor man's level shifter), but I would not short them, better do what I do just now :) -> replace those 1k resistors with 22-47ohm resistors in all 4 SPI Sdcard s...
by RogerClark
Mon Jun 26, 2017 11:30 am
Forum: Projects
Topic: OV7670, Generic STM32F103RC and ILI9341 display
Replies: 84
Views: 6493

Re: OV7670, Generic STM32F103RC and ILI9341 display

But can we trigger DMA on an (rising/fallig) edge of an input signal (PCLK)? I think we could count the input signal edge with a timer set up in slave trigger mode, which timer output can then work as DMA trigger source, as I mentioned already here: http://www.stm32duino.com/viewtopic.php?f=19&t=4#...
by RogerClark
Mon Jun 26, 2017 7:36 am
Forum: Projects
Topic: OV7670, Generic STM32F103RC and ILI9341 display
Replies: 84
Views: 6493

Re: OV7670, Generic STM32F103RC and ILI9341 display

OK. I checked, and XCLK is is showing as 33mhz on my analyser but it must mean 36Mhz (72Mhz /2) Pixel clock seems to be 2.25Mhz i.e DIV16 of 36Mhz @ 12 FPS If I change the framerate, to 7.2 FPS, the Pixel clock changes to 1.51 Mhz (I presume this is 36Mhz DIV24 ) Back on 12 FPS QQVGA There is a huge...
by RogerClark
Mon Jun 26, 2017 7:07 am
Forum: General discussion
Topic: Should we still use optimisation level -Os (Small)
Replies: 15
Views: 192

Re: Should we still use optimisation level -Os (Small)

zoomx wrote:
Mon Jun 26, 2017 6:29 am
It is not possible to change the optimization in the Tools menu?
I think it should be possible to do that, but it means you have to manually set this for each sketch in case it needs to be small or needs to be fast.
by RogerClark
Mon Jun 26, 2017 7:06 am
Forum: Projects
Topic: OV7670, Generic STM32F103RC and ILI9341 display
Replies: 84
Views: 6493

Re: OV7670, Generic STM32F103RC and ILI9341 display

I will check the clocks using my logic analyzer Re: Reading and writing at the same time. It would be more efficient to byte swap as it reads the pixels, and also to pixel duplicate, and perhaps even to duplicate the line into a buffer. This would leave more time for done other processing, but on a ...