pzw Posted May 20, 2018 Posted May 20, 2018 I'm currently designing a PCB which will use a nanopi duo board. Unfortunately it is not in stock at the moment so I can't order one yet to verify some measurements. Can someone (@guidol or @larry bank maybe?) who has one sitting on their desk please give me the following info; - Distance between headers. Total width is 1" so I guessed 0.9"... Is this correct? - length of the pin headers. So I know how high it will sit on the PCB - total height of the pins + PCB - is there anything on the bottom PCB which is higher than the plastic on the pin headers? In other words; can I push the whole module all the way down to a PCB and then only have the thickness of the plastic of the pin headers? Or is something "sticking" out.. - How much does the heatsink add to the total thickness? (Or what is the thickness of the heatsink...) Thanks in advance for your help and time.
squarefoot Posted May 21, 2018 Posted May 21, 2018 Take a look to the relevant wiki at Friendlyarm site: http://wiki.friendlyarm.com/wiki/index.php/NanoPi_Duo There's a .dxf CAD file which should help at least with the distance between headers. I'm also waiting for the Duo to become available again, 3 to 4 weeks seems a long time though.
guidol Posted May 21, 2018 Posted May 21, 2018 Can someone (@guidol or @larry bank maybe?) who has one sitting on their desk please give me the following info; - Distance between headers. Total width is 1" so I guessed 0.9"... Is this correct? 24mm - length of the pin headers. So I know how high it will sit on the PCB 2mm plastic (yellow) & 6mm the metal pins - total height of the pins + PCB 12mm - is there anything on the bottom PCB which is higher than the plastic on the pin headers? In other words; can I push the whole module all the way down to a PCB and then only have the thickness of the plastic of the pin headers? Or is something "sticking" out.. the uSD-port is below the plastic of the headers BUT the screws for the heat sink are 0.5-1mm higher than the yellow plastic - How much does the heatsink add to the total thickness? (Or what is the thickness of the heatsink...) the heat-sink does add around 4mm - so the total thickness is 16mm
pzw Posted May 21, 2018 Author Posted May 21, 2018 Great! That's all the information I was looking for! Thanks a lot @guidol
pzw Posted May 28, 2018 Author Posted May 28, 2018 I have one more question, which I hope @guidol can help with too... If I read the datasheet of "magjacks" made by Pulse (that is a connector with built in transformers / magnetics) I see the following; There is clearly an set of resistors terminating the lines from the magjack to the PHY (in the H2+)... However on the diagrams there is nothing like this; So I hope that someone can measure for me the resistance between pin 13&14 on the headers of the DUO when it is not plugged into a shield. If there is a resistance of about 100ohms, it means that these resistors are built into the CPU... If not, then I need to add them. (And FriendlyArm might need to revise their shield or module ;-) ) Thanks in advance!
chwe Posted May 28, 2018 Posted May 28, 2018 did you look into the schematics from their shield for the duo? http://wiki.friendlyarm.com/wiki/images/5/55/Schematic_-_Mini_Shield_for_NanoPi_Duo.pdf
pzw Posted May 28, 2018 Author Posted May 28, 2018 @chwe the snippets in my post come from their diagram of the module... I noticed forgot to add the snippets from the shield.. I'll add it when I'm home again. But that will show no termination circuit...
chwe Posted May 28, 2018 Posted May 28, 2018 from their diagram for the NanoPi, but not from the minishield where ETH is populated... 26 minutes ago, chwe said: http://wiki.friendlyarm.com/wiki/images/5/55/Schematic_-_Mini_Shield_for_NanoPi_Duo.pdf
guidol Posted May 28, 2018 Posted May 28, 2018 2 hours ago, pzw said: I have one more question, which I hope @guidol can help with too... So I hope that someone can measure for me the resistance between pin 13&14 on the headers of the DUO when it is not plugged into a shield. If there is a resistance of about 100ohms, it means that these resistors are built into the CPU... If not, then I need to add them. (And FriendlyArm might need to revise their shield or module ;-) ) between Pin 13 & 14 the ohm-meter doesnt show a reaction - like there is no connection between these two pins. Did try also both directions (+/-) NO zero Ohm and NO 100 Ohm 1
pzw Posted May 28, 2018 Author Posted May 28, 2018 Thanks @guidol! Last question. Was that powered up?
guidol Posted May 28, 2018 Posted May 28, 2018 19 minutes ago, pzw said: Thanks @guidol! Last question. Was that powered up? no [EDIT] with power via MicroUSB there are 105-120 Ohm - ALL measured without the base, BUT the picture for finding the right pins....with heatsink I couldnt read at the top of the Duo 1
pzw Posted May 28, 2018 Author Posted May 28, 2018 Great news! Thanks @guidol. Saves me a headache.. haha .. I suspected that the termination might be in the h2+ ... Thanks for confirming this..
chwe Posted May 28, 2018 Posted May 28, 2018 1 hour ago, pzw said: Saves me a headache. Hmm I'm not a EE but wasn't this clear from the schematics (as far as I understand schematics this was clarified in the minishield part of it). Hmm lets ask a EE... @TonyMac32
pzw Posted May 28, 2018 Author Posted May 28, 2018 @chwe In the schematics it was not clear if there is a termination circuit inside the CPU... The headache referred to the required implementation of a termination circuit in my design.
pzw Posted May 28, 2018 Author Posted May 28, 2018 @TonyMac32 Thanks for verifying it :-) . It did strike me as odd if FA would have overlooked this termination requirement... Also I would have expected network throughput issues because of it, but I couldn't find reports about that... So that made it almost certain that the termination was happening on the die.
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