OMAP5432 EVM serial port, and boot


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Hi !

I connected a micro USB cable to what it seems to be the serial port.
I see no new tty device and I don't know how to access it from my main computer.


 
 
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I use minicom, it should show up as /dev/ttyUSB0 and act like a typical tty device.

I've had it at times where a non-bootable SD card will brick up even looking at the u-boot prompt.

Edit: aTc stores his builds on site, I believe I'm currently running the Jessie image with the 4.1 Kernel. 
rootfs here: http://next.openpandora.org/omap5/rootfs/
Kernels here: http://next.openpandora.org/omap5/kernel/

Edit: Also I believe aTc rootfs image now is done on a single ext4 partition and doesn't require a fat formatted boot partition
 
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The debug port works even when the board is off (FTDI is always powered by USB cable), so you either have a hardware problem or something's bad with the host. You can connect it to pandora and ttyUSB0 should appear on it (on default firmware).
 
Code:
[  226.468107] usb 4-2.2: new full-speed USB device number 5 using ohci_hcd
[  226.551021] usb 4-2.2: not running at top speed; connect to a high speed hub
[  226.561012] usb 4-2.2: New USB device found, idVendor=0403, idProduct=6010
[  226.561015] usb 4-2.2: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[  226.561017] usb 4-2.2: Product: Dual RS232-HS
[  226.561020] usb 4-2.2: Manufacturer: FTDI
[  226.561123] usb 4-2.2: rejected 1 configuration due to insufficient available bus power
[  226.561125] usb 4-2.2: no configuration chosen from 1 choice
 
Plugged directly on my motherboard, I now see /dev/ttyUSB0 and /dev/ttyUSB1. Why two ?
 
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[ 226.468107] usb 4-2.2: new full-speed USB device number 5 using ohci_hcd
[ 226.551021] usb 4-2.2: not running at top speed; connect to a high speed hub
[ 226.561012] usb 4-2.2: New USB device found, idVendor=0403, idProduct=6010
[ 226.561015] usb 4-2.2: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[ 226.561017] usb 4-2.2: Product: Dual RS232-HS
[ 226.561020] usb 4-2.2: Manufacturer: FTDI
[ 226.561123] usb 4-2.2: rejected 1 configuration due to insufficient available bus power
[ 226.561125] usb 4-2.2: no configuration chosen from 1 choice

Is that on the Pandora? or other device... On the Pandora my guess you would need a Hub as TTY devices are USB 1.0
 
Nope, It was plugged on the PC through a sort of hub, which is working well with the USB/DB9 cable I use with the IGEP.
 
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I use this but only see a stream of strange characters :

Code:
minicom -D /dev/ttyUSB0 -b 115200 -8
 
Code:
my current setup:
Code:
Welcome to minicom 2.6.1                                                  
                                                                          
OPTI+-----------------------------------------------------------------------+
Comp| A -    Serial Device      : /dev/ttyUSB0                              |
Port| B - Lockfile Location     : /var/lock                                 |
    | C -   Callin Program      :                                           |
Pres| D -  Callout Program      :                                           |
    | E -    Bps/Par/Bits       : 115200 8N1                                |
    | F - Hardware Flow Control : No                                        |
Debi| G - Software Flow Control : No                                        |
    |                                                                       |
tras|    Change which setting?                                              |
    +-----------------------------------------------------------------------+
            | Screen and keyboard      |                                  
            | Save setup as dfl        |                                  
            | Save setup as..          |                                  
            | Exit                     |                                  
            +--------------------------+
 
My SYSBOOT switch configuration was bad !
Looks like 0 and 1 are reversed on the documentation, because I should now have this boot order :
UART,OneNAND,N/A.

Well thanks anyway !

Oh, and why do I also see a /dev/ttyUSB1 ?
 
I don't know about the OMAP5 EVM but one of the STM boards I played with a couple years ago had ttyUSB0 for debug and ttyUSB1 as the actual serial port for the chip.  Could be the same thing?
 
My SYSBOOT switch configuration was bad !
Looks like 0 and 1 are reversed on the documentation, because I should now have this boot order :
UART,OneNAND,N/A.

Well thanks anyway !

Oh, and why do I also see a /dev/ttyUSB1 ?

Oh right... I kind of remembered that as well.

Not sure why you would see a ttyUSB1... I know at times if you unplug and plug back in quickly it doesn't have enough time to free up the ttyUSB0 device before it creates another in this case ttyUSB1... but that is just a guess.

edit: hmm I see a ttyUSB1 as well on my end... 
 
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Ok.

About the kernels, there's no EVM-explicit one. Which one (preferably the latest) should I use ?
 
Ok.

About the kernels, there's no EVM-explicit one. Which one (preferably the latest) should I use ?

Well I'm using the latest one aTc pushed for the pyraOS, I know he's working on something newer, but this is the last thing he shared to the public: 
4.1-rc5-gta04-a.tar.xz
 
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Can you tell me where you get those to start the 4.1 plz ?
MLO
u-boot.bin
the .dtb

Do you use a uEnv.txt ?

Funny thing is my IGEP SD cards boot.

--Edit :
Looks like it's http://next.openpandora.org/omap5/kernel/u-boot-2015-04-rc5-py.tar.xz for u-boot.img and MLO, and I suppose that the .dtb is the one from the kernel archive.

About u-boot, is the install procedure needed (didn't do that on IGEP) ?
 

Code:
install :

(run on devboard, mmcblk0 is the emmc), 

export DISK=/dev/mmcblk0

sudo dd if=/dev/zero of=${DISK} bs=1M count=10

sudo dd if=./MLO of=${DISK} count=1 seek=1 bs=128k
sudo dd if=./u-boot.img of=${DISK} count=2 seek=1 bs=384k
 
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I followed a more strict procedure while adapting my custom makesd script.
I now see the u-boot menu when starting the board.
 
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