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Please help with SAM-BA monitor problem

Posted: Mon Dec 12, 2016 10:09 am
by 666666
I tried SAM-BA monitor for atmel at91samxxxx chips

I'm working with non-atmel board using at91sam7s128 , I tried the monitor program with board option : at91sam7s128 and noboard but neither of them works they are not responding ?!

My computer recognized the chip and I tried the board on both windows xp and linux :

In linux I have this when I put in terminal lsusb :

Bus 005 Device 008: ID 03eb:6124 Atmel Corp. at91sam SAMBA bootloader

and in windows I installed the driver and board is recognized in serial port category .

So if my computer recognize the chip and SAM-BA therefor do every thing must be ok ?

I also tried SAM_I_AM ,it successfully open a communication with my board using 'open command' but when I give a command like 'info usb' it gives me 'Error: SAM-BA not responding'

in my board I used some estimate value , in specific :

I used 31 ohm resistors instead of 27 ohm for DP-DM .
I used 12pf capacitors instead of 15pf for DP-DM .
I used 1.47k resistor in pll RC loop instead of 1.5k .which maybe sounds good as what the pll calculator says .
and I used 12pf load capacitors instead of 10pf load capacitors for 18.432MH crystal .
and this schematic shows all parts related to usb in my board :
is there any thing could help me to indicate the problem ? also I have some fears about FDN360P maybe it is slow in switching , but datasheet didn't said any things on how fast pulling up will be .

Re: Please help with SAM-BA monitor problem

Posted: Mon Dec 12, 2016 10:59 pm
by tsvoipio
If your crystal is 18.432 MHz, it may be impossible to create a proper 48 MHz (+/- 0.25%) USB clock from it.