Posts by JohanHellemans

Hi,

There used to be a good document PicoCOM5_Linux_V0.1.pdf describing line by line how to get started with the PicoCOM5. Is this already available for the PicoCOMA5? Can't find it in the download area.

Thx,
Johan Hellemans

Hi,

As the PicoCOMA5 should be pin compatible with the PicoCOM3, can we keep on using the STARTINTF2 starterkit for our evaluation and development?
Are there any good reasons to switch over to the PicoCOMA5-SKIT?

Thx

Hello,

Any update?

Best regards

Hi,

For some reason, it seems that the TTL levels are not correct on this ttySAC2. The signal does not go below 1.7V.
I have tried this on more than one picocom, on the development board, I removed the resistor in series and attached a wire for measurement, so nothing else is attached to it anymore.

Could you try to reproduce, please advice.

Hi,

Any update on the Linux 3.3 Kernel for PicoCOM3?
Any target date?

Thx

Hi,

In the PicoCOM3 Hardware guide, pin 24 has the name IO7 USB PWR. But in the GPIO Reference Card, this pin does not have a GPIO name or a /sys/class/gpio number.
Is this pin somehow accessible as GPIO?

I hope it is, since our hardware engineer assumed a pin with name IO7 to be a software configurable IO pin.

Any advice how to use this pin?

Thanks

Hi,

We only use the USB host functionality in our system. Pins 21-22-23-24 are not connected as we do not need USB device functionality.

The USB hub is indeed connected to the pins 19-20.

I think the problem is indeed located in the different software. Are there any plans to update the PicoCOM3 software? How difficult would it be to port the PicoCOM5 software to the PicoCOM3? Anyone who can help me with that?

As the problem (in PicoCOM3) is seen as well during uBoot as during kernel startup, maybe we can first try to concentrate on getting it to work in the uBoot. Could you try updating that to more recent USB drivers?

Any other suggestions of where I should look?

This is a complete show stopper! This used to work fine on PicoCOM5.

Thanks for any help.

Hi,

I would like to make use of all three UARTs. Is there anything special I should configure?

Right now, it seems I have

ttySAC0 is functional on pins 13, 14 (COM2)

ttySAC1 is functional on pins 17, 18 (COM1)

But I can't seem to get any output on pins 15, 16 COM3 (COM2 RTS/CTS).

Did not make changes to builtroot rootfs yet. These are in /dev:
crw-rw---- 1 root root 204, 64 Jan 1 00:00 ttySAC0
crw------- 1 root root 204, 65 Jan 1 00:00 ttySAC1
crw-rw---- 1 root root 204, 66 Jan 1 00:00 ttySAC2
crw-rw---- 1 root root 204, 67 Jan 1 00:00 ttySAC3

Thx.

Hi,

The problem is seen on our own hardware, not the evaluation board. It is an error, it is a major problem for us.

We have an on-board USB hub (TUSB2046BIVRF) connected to the PicoCOM3, it is always connected hardwarewise. On PicoCOM5, I had no problems with it, it enumerated and USB devices on the hub (on-board FTDI usb to serial chips) also enumerated.

Now, switching over to PicoCOM3, which was promised to be pin compatible, suddenly the USB hub does not want to enumerate anymore! So also devices attached to it are not visible anymore.

If I looked it up correctly, -62 indicates timeout ETIME. It is not a problem of the board or hardware, just plugging in the PicoCOM5 and everything works.

Could you please check the differences between the PicoCOM3 and PicoCOM5 low level USB software?

Best regards,
Johan Hellemans

Thanks for the quick reply, but it does not solve my problem.
Actually, I don't mind about the USB device being accessible during U-boot, but the USB hub (tusb2046bifr) also gives problems while booting the kernel:

VFS: Mounted root (jffs2 filesystem) readonly.
Freeing init memory: 124K
usb 1-1: new full speed USB device using s3c2410-ohci and address 2
usb 1-1: device descriptor read/64, error -62
usb 1-1: device descriptor read/64, error -62
usb 1-1: new full speed USB device using s3c2410-ohci and address 3
usb 1-1: device descriptor read/64, error -62
usb 1-1: device descriptor read/64, error -62
usb 1-1: new full speed USB device using s3c2410-ohci and address 4
usb 1-1: device not accepting address 4, error -62
usb 1-1: new full speed USB device using s3c2410-ohci and address 5
usb 1-1: device not accepting address 5, error -62
hub 1-0:1.0: unable to enumerate USB device on port 1
Starting portmap: done
Initializing random number generator... done.
Starting network...

The strange thing is that I had no problem with this device on PicoCOM5.
I am still missing something in my kernel, or (as it also fails in the u-boot) is there really no hardware difference between PicoCOM5 and PicoCOM3? Last time I saw something similar, it was because D+ and D- were swapped on one of the ports after the hub.

Thanks,
Johan

Hi,

While testing our application (own developed hardware) with the PicoCOM3, which should be pin compatible with the PicoCOM5, I see problems with the USB devices that I did not have on PicoCOM5:
usb 1-1: new full speed USB device using s3c2410-ohci and address 2
usb 1-1: device descriptor read/64, error -62
usb 1-1: device descriptor read/64, error -62
usb 1-1: new full speed USB device using s3c2410-ohci and address 3
usb 1-1: device descriptor read/64, error -62
usb 1-1: device descriptor read/64, error -62
usb 1-1: new full speed USB device using s3c2410-ohci and address 4
usb 1-1: device not accepting address 4, error -62
usb 1-1: new full speed USB device using s3c2410-ohci and address 5
usb 1-1: device not accepting address 5, error -62
hub 1-0:1.0: unable to enumerate USB device on port 1

Looking at the differences between evaluation board and our board, I see an error in the U-Boot:
USB: scanning bus for devices...
USB device not responding, giving up (status=20)
I looked this up on the internet and tried out the patch described on <!-- m --><a class="postlink" href="http://plugcomputer.org/plugforum/index.php?topic=891.0">http://plugcomputer.org/plugforum/index.php?topic=891.0</a><!-- m --> but with no success.
I also tested with USB disabled in U-boot, but with no success.

Anyone some ideas?

Hi,

So I assume changing /arch/arm/mach-sp5pc100/mach-picocom5.c enable a spidev0:

But after recompiling & flashing the Kernel, I cannot find the spidev0.
In /sys/devices/platform/s3c64xx-spi.1, there is only a spi1.0 device with the mcp251x modalias...

Any ideas?

Best regards

Hi,

I could use some help with the SPI.

Documentation says "signals are shared with the on module CAN controller".
Does this mean that I do not need to modify the /PicoCOM5-Linux_V0.1-2.6.29/arch/arm/mach-s5pc100.c file?
If that is the case, I tried mknod /dev/spidev1.0 c 153 0, but it fails to open the file from code. (same when I try mknod /dev/spidev1.1 c 153 1). When doing mknod, file permissions are 644, chmod to 666 also doesn't help.

Or do I have to add 'my' device to the spi_board_info devs array? Is it because the interface 0 is already registered by the CAN, that I cannot "mknod it anymore"?
In that case, what is the busnumber? I assume it would be the same (1) as the mcp251x CAN? But in the mach-s5pc100 it mentions bus_num 0 for a commented out MMC device?
What should the chip_select be? I would assume 0 as pin29 is called SPI_PCS0, but the CAN is also on chip select 0...?

Any advice, sample code perhaps?

Thanks,
Johan

Hi,

Documentation states that there is demo source code for uart / gpio / ... located in the download area...
Is it there already? Where?

Is there also some information on how to change the processor speed (in order to save some power)?

Regards,
Johan Hellemans

Hi,

It works now, when programmed on another PC. Although I already tested it on an XP machine instead of a win 7, I found it to work perfectly when programmed by yet another win xp machine.

I will post more info if I find out more about this.

Thanks for the support!

Hi,

I tested with three more modules (labelled linux now) and 2 different evaluation boards, still have the same problem on all of them.
So I suppose this is not a hardware issue, but a configuration / software issue. There must be something wrong in what I do, something missing in the documentation (PicoCOM5_Linux_V0.1.pdf), or in the images provided (zImage_PicoCOM5_V0.1), or …

Could you reproduce exactly the steps I took (see earlier posts), starting from a completely erased device, and including a printenv? Maybe something was overlooked?

Thx

Hi,

Yes, after my first trial of getting Linux on the board, I verified that WinCE was working and it did.
Do you really have to order a different PicoCOM for Linux?
The PicoCOM5_Linux_V0.1 documentation states that you can switch from Windows Embedded CE to Linux.
I did not flash the n-boot myself, but it seems I have the latest version.

Thx

Hi,

This is the whole thing from scratch:

On the board, I'm only using COM1 on J6, ethernet and 5V, no touchscreen attached.
My PicoCOM5 is labelled WindowsCE, but from the documentation I understand it should not make a difference and be able to run linux right|?

Could this be hardware related, I only have one set.

Thx

Hi,

Thanks for the quick response.

The output is indeed what I stated:

I also rebuild the kernel but with the same result.
Where is the output from the kernel boot to be seen? On the console; COM1 or on the touchscreen?

PS: don't seem to find the PicoCOM5_Buildroot.pdf...

Hi,

Just received the PicoCOM5 together with its evaluation board. WinCE works good, but I need Linux.
All goes fine following the document PicoCOM5_Linux_V0.1.pdf. But then, the only thing I get is:

And after that nothing anymore, no error, nothing. I would assume the output of the kernel boot process to appear on the same COM1 (bootargs=console=ttySAC1,38400 ...) right?

I did the 'run bootlocal'. Even changing the bootargs to something bogus does not produce any error.

In U-boot, iminfo gives Unkown image format for both 20000000 and 21000000. Bootm result in the same as above.

I must be missing something, any help much appreciated.

Thanks,
Johan Hellemans