im6 Ultra Lite Booting Issue

[krunalshah]

Hi

We have developed customized board based on EVK of imx6 Ultralite.We have used processor MCIMX6G2DVM05AA and we are using micro Sd card to boot the board. RAM which we are using is AS4C256M16D3L-12BCN from Alliance memory. We have only microsd card for booting and USB for communication to my main board , UART and MFG_Boot portion we have used on our board.

Now when we are trying to boot the device after power up, we are not able to boot it but as soon as we touch the POR_B test point with probe (Please note the at probe's other end is open, means one end we are touching on the Test point of POR_B and other end of cable is open) system starts booting up and complete the process.

We do not know what prob is doing so that system started booting up. We have tried 10K & 4.7K for BOOT Mode 1configuration to pull high as described in manual and evk manual.

We have captured some wave form as attached, please help us to find the solution.

Thank@

Krunal Shah

[igorpadykov]

Hi Krunal

these documents do not give any usful info, please provide

oscilloscope diagrams from power names in

Table 10. Operating Ranges i.MX6UL Datasheet

http://cache.freescale.com/files/32bit/doc/data_sheet/IMX6ULCEC.pdf

also you can try all suggestins given on similar issue

IMX6 Solo intermittent boot-up failures 

In that case another customer fixed issue by rerunning ddr tester and

finding more accurate calibration settings.

As additional test suggest to remove R83C81 and solder temporarily

circuit from i.MX6UL EVK design

Best regards
igor

[krunalshah]

Dear Igo

Please find the attached waveform for different power rails.

Please note all are in reference of VDD_SNVS_IN

Please note the full name of the wave forms as below,

1) VDD_SNVS_I is VDD_SNVS_IN

2) VDD_HIGH_I is VDD_HIGH_IN

3) ARM_SOC is VDD_ARM_SOC_IN

4) VDD_ARM_C is VDD_ARM_CAP

5) VDD_SOC_C is VDD_SOC_CAP

6) VDD_HIGH_C is VDD_HIGH_CAP

Thanks

Krunal Shah

Syntrons Technologies Pvt Ltd.

407, Safal Prelude,

Corporate Road,

Prahaladnagar,

Ahmedabad 380015

(M) +91-9427961799

[igorpadykov]

Hi Krunal

power up sequence seems as correct. For improving

POR waveform could you attach 1K
on R83 and test again, so POR rise time was fast.

Best regards
igor

[krunalshah]

Dear Igor

Ok, we will change it and check it.

While we are evaluating our board last night, we found below scenario.

When we are in MFG_BOOT mode, uboot is showing a message as " No SC Cad Present" while boot start. but we can write in the card, and in second POR it gets boot as well.

Why this message is displayed and how to rectify the same.

See the attached log files , in Ourboard.doc file i have highlighted the error which we are getting. The same SD card's log in EVK is also attached for your reference.

Thanks

Krunal Shah

[krunalshah]

Dear Igor

We tried with 1k @ R83, but system is not a all booting even after 10 POR. We also tried 10k and system is booting up in second POR only. No luck to solve the problem

Is there any updates from your side for both front, ON POR and we are not able to detect SD card in MFG BOOT as per my previous comments.

Thanks

Krunal Shah

[igorpadykov]

Hi Krunal 

please attach jtag after boot fail and check  SRC_SBMR1

SRC_SBMR2 registers: they should have correct boot configuration.

Best regards
igor

[igorpadykov]

Hi Krunal

this may be caused by incorrect power-up sequence, suggest

to check all power lines with oscilloscope.

Check that there were no sags, in particular in VDD_HIGH_IN and

just for test set VDD_HIGH_IN first in sequence along with VDD_SNVS_IN.

Best regards
igor

[krunalshah]

Dear Igor

Can yo please let us know where our sequence is not correct, i am

attaching documents for the same.

Thanks

Krunal Shah

Syntrons Technologies Pvt Ltd.

407, Safal Prelude,

Corporate Road,

Prahaladnagar,

Ahmedabad 380015

(M) +91-9427961799

[igorpadykov]

Hi Krunal

one can try to extend POR, also please check i.MX6UL ERR009455 Clock:
24 MHz Oscillator does not startup.

Best regards
igor

[krunalshah]

Dear Igor

One more finding as below,

/_*

*_/

/_On Our Designed Board_/

Step 1) We have disconnected POR from reset IC and Connected POR pin

directly to one switch and other end of the switch is connected to the

ground.

Step 2) Now when we turn on the power of our system we have pressed

(Short ) that switch so POR will be low on power up

Step 3) After few milliseconds/second when we release (open) that switch

, so POR is high now, but the system is not booting from SD card.

at this time processor enters in ti serial boot mode,MFG tool detect

HID-Compliant device.

Step 4) When we press the switch again and release it , system boots

perfectly from SD card.

*In nutshell, when POR is high First time system is not booting from SD

card and enters in to Serial Boot Download Mode, but when POR is high

second time System boots perfectly from SD Card.*

/_*

*_/

/_On imx6 Ultra Lite EVK_/

Step 1) We have disconnected POR from reset IC and Connected POR pin

directly to one switch and other end of the switch is connected to the

ground.

Step 2) Now when we turn on the power to our system we have pressed

(Short ) that switch so POR will be low on power up

Step 3) After few milliseconds/seconds/minute we release (Open) the

switch, so POR is high now and system is booting up perfectly.

Can you please help us to find why our system needs second POR while you

EVK needs only one POR?

Thanks

Krunal Shah

Syntrons Technologies Pvt Ltd.

407, Safal Prelude,

Corporate Road,

Prahaladnagar,

Ahmedabad 380015

(M) +91-9427961799

[krunalshah]

Dear Igor

We have checked the ERR009455 and check our clock signals.Please see the

attached wave form of our 24MHz of our board.

Kindly note we are using APX809-26SAG-7 as external Reset IC, because on

our board we have not place any reset IC.

I am also attaching our power section & POR section's schematic & power

sequence in excel sheet.Can you please review and let me know if there

some improvement or changes needed for to get proper boot sequence.

Thanks

Krunal Shah

Syntrons Technologies Pvt Ltd.

407, Safal Prelude,

Corporate Road,

Prahaladnagar,

Ahmedabad 380015

(M) +91-9427961799

[krunalshah]

Dear Igor

We have not installed 32.768kHz crystal on our board, will it create any problem for POR_B too boot up? Do we compulsorily needed it on the board?

Thanks

Krunal Shah

[igorpadykov]

Hi Krunal 

please check sect.4.5 Avoiding reset pitfalls  Hardware Development Guide for the
i.MX 6UltraLite Applications Processor

http://cache.freescale.com/files/32bit/doc/user_guide/IMX6ULHDG.pdf

Seems board has much noise so one can attach C503 about 1uF(or more,

find experimentally) or try install 1K R519 SPF-28617
Schematics (1)
MCIMX6UL-EVK_DESIGNFILES
Design files, including hardware schematics, Gerbers, and OrCAD files. (REV 0)
http://www.nxp.com/products/sensors/gyroscopes/i.mx6ultralite-evaluation-kit:MCIMX6UL-EVK?fpsp=1&tab...

Best regards
igor
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[krunalshah]

Dear Igor

We have tried both options but still have the same issue. Will there be

any issue of PCB Buildup/Material ?

Thanks

Krunal Shah

Syntrons Technologies Pvt Ltd.

407, Safal Prelude,

Corporate Road,

Prahaladnagar,

Ahmedabad 380015

(M) +91-9427961799