Fitting RTC - 18 pin connector on 14 pin header WTF?

Discussion of official MiSTer Project addons. (https://github.com/MiSTer-devel/Hardware_MiSTer)


scyto
Posts: 11
Joined: Fri Feb 05, 2021 11:17 pm
Has thanked: 2 times
Been thanked: 1 time

Fitting RTC - 18 pin connector on 14 pin header WTF?

Unread post by scyto »

Ok so the RTC has 18pin connector, the DE board has a 14 pin header.
None of the guides i have found detail what the pin alignment should be, can anyone shed some light - there are 3 options for how it can be connected.
a) centered
b) post side justified
c) ram side justified

My DE board- has a plastic shroud around the pins so if pin 1 is marked it is not visible (and makes fitting the RTC like really hard).
User avatar
darksakul
Posts: 353
Joined: Mon May 25, 2020 4:34 pm
Has thanked: 397 times
Been thanked: 73 times

Re: Fitting RTC - 18 pin connector on 14 pin header WTF?

Unread post by darksakul »

Are you looking at the right header?
It's the header with the "box" around it.

You want the LTC header, not the ADC header
layout_top.jpg
layout_top.jpg (464.82 KiB) Viewed 4120 times
It is my great regret that we live in an age that is proud of machines that think and suspicious of people who try to.
User avatar
jlancaster86
Posts: 148
Joined: Sat Jun 27, 2020 1:33 pm
Has thanked: 130 times
Been thanked: 35 times

Re: Fitting RTC - 18 pin connector on 14 pin header WTF?

Unread post by jlancaster86 »

I don't have an RTC board myself, but it looks to me that it should be a matter of lining up the plastic of the connector to fit inside the header, so that only the centre 14 holes on the connector actually are mating with pins.
scyto
Posts: 11
Joined: Fri Feb 05, 2021 11:17 pm
Has thanked: 2 times
Been thanked: 1 time

Re: Fitting RTC - 18 pin connector on 14 pin header WTF?

Unread post by scyto »

Thanks,

Yes look at the LTC header, count the pins on the LTC header then go count the pins on any of the RTC clock modules you see for sale - the clock module has more pins.

The answer it turns out it center justified, also the pressure of the connector on the outside edges of the header plastic (plastic you see around the pins) will break the plastic - at least it did with my RTC module i got.
Attachments
20210612_174450757_iOS.png
20210612_174450757_iOS.png (9.56 MiB) Viewed 4016 times
scyto
Posts: 11
Joined: Fri Feb 05, 2021 11:17 pm
Has thanked: 2 times
Been thanked: 1 time

Re: Fitting RTC - 18 pin connector on 14 pin header WTF?

Unread post by scyto »

jlancaster86 wrote: Sat Jun 12, 2021 4:07 am I don't have an RTC board myself, but it looks to me that it should be a matter of lining up the plastic of the connector to fit inside the header, so that only the centre 14 holes on the connector actually are mating with pins.
all header in all electronics i have ever done you line p1 with p1 - thats not possible in this case so totally non intutive - basically none of these RTCs are actually designed to go on a DE10 board - wrong # of pins, wrong size header etc - they are just generic modules for a pi or some such.
wodmarach
Posts: 21
Joined: Thu Apr 15, 2021 8:50 pm
Been thanked: 7 times

Re: Fitting RTC - 18 pin connector on 14 pin header WTF?

Unread post by wodmarach »

It's an 18pin header socket just with 14 pins connected... Think about what you just asked. Do you really think a header the right size to fit a socket needed to be moved sideways and the socket cut away to fit?
scyto
Posts: 11
Joined: Fri Feb 05, 2021 11:17 pm
Has thanked: 2 times
Been thanked: 1 time

Re: Fitting RTC - 18 pin connector on 14 pin header WTF?

Unread post by scyto »

wodmarach wrote: Sat Jun 12, 2021 6:00 pm It's an 18pin header socket just with 14 pins connected... Think about what you just asked. Do you really think a header the right size to fit a socket needed to be moved sideways and the socket cut away to fit?
I am not a effing idiot - that's why i asked, to check, these are what all the RTC clock modules are like.
Basically folks are selling RTC modules that don't fit. ¯\(°_o)/¯
If they fitted, the natural pressure of the connector wouldn't have broken the header shroud - would it.
I was asking because it was apparent the connector would break the header shroud.

But thanks for you condescension, what awesome friendly community.
pdxubaru
Posts: 1
Joined: Sat Jun 12, 2021 6:50 pm
Has thanked: 3 times
Been thanked: 1 time

Re: Fitting RTC - 18 pin connector on 14 pin header WTF?

Unread post by pdxubaru »

I purchased a cheap RTC from Amazon. It didn't fit and I didn't care to try and force it, the plastic was too wide one way and too thin the other, just like in the picture above. I ordered another from a reputable website (not sure of forum rules and I'm too lazy to read them, no affiliation with the site nor do I get kickbacks... are there DMs in this forum? feel free to dm me) but it fit without any extra force. I don't think it will break the plastic under normal usage. If your RTC doesn't fit, return it and get one from somewhere you can trust. The DE10-Nano isn't getting any cheaper. The black one fits and works.
To say ALL RTC have the same pins is not true.  You get what you pay for.
To say ALL RTC have the same pins is not true. You get what you pay for.
C414F736-BD5B-492E-B136-F6DF60438273.jpeg (3.13 MiB) Viewed 3930 times
Another slight size difference…
Another slight size difference…
631739A0-642A-4B6C-B698-3DFA55033812.jpeg (2.45 MiB) Viewed 3930 times
Slight size difference…
Slight size difference…
4855C1BF-862A-4CB3-9986-6A8E6BAB7478.jpeg (2.79 MiB) Viewed 3930 times
No broken plastic here
No broken plastic here
0ACECBF2-1380-4B5A-8D10-813CAE1C508A.jpeg (2.9 MiB) Viewed 3930 times
wodmarach
Posts: 21
Joined: Thu Apr 15, 2021 8:50 pm
Been thanked: 7 times

Re: Fitting RTC - 18 pin connector on 14 pin header WTF?

Unread post by wodmarach »

What you actually said was and I quote
None of the guides i have found detail what the pin alignment should be, can anyone shed some light - there are 3 options for how it can be connected.
a) centered
b) post side justified
c) ram side justified
Which to anyone reading it comes across exactly as I said. You ASKED how a header designed to fit the socket dead center was supposed to be aligned you did NOT say "guys this header looks too big without breaking the socket are you sure it's right?"
User avatar
legacypixels
Posts: 91
Joined: Sun May 24, 2020 9:20 pm
Has thanked: 25 times
Been thanked: 25 times

Re: Fitting RTC - 18 pin connector on 14 pin header WTF?

Unread post by legacypixels »

wodmarach wrote: Sat Jun 12, 2021 6:58 pm What you actually said was and I quote
None of the guides i have found detail what the pin alignment should be, can anyone shed some light - there are 3 options for how it can be connected.
a) centered
b) post side justified
c) ram side justified
Which to anyone reading it comes across exactly as I said. You ASKED how a header designed to fit the socket dead center was supposed to be aligned you did NOT say "guys this header looks too big without breaking the socket are you sure it's right?"
Not aware of where OP purchased their RTC board, but....

There are a lot of sellers (ebay, ali, etc) that are using cheap knock off headers on their RTC boards. I've tested a bunch of brands, and the only connectors that fit correctly are the legit Amphenol headers. They are quite a bit more expensive, but you need to use them to build the board properly.

The knock offs are hard to line up, and are slightly oversize, and will crack the de-10 housing when forced into place. Just one more issue with the poorly made boards floating about.
US based seller of MiSTer addon boards. Visit https://www.legacypixels.com/mister
MiSTerFit
Posts: 1
Joined: Wed Jun 16, 2021 8:03 pm
Has thanked: 1 time

Re: Fitting RTC - 18 pin connector on 14 pin header WTF?

Unread post by MiSTerFit »

pdxubaru wrote: Sat Jun 12, 2021 6:55 pm The DE10-Nano isn't getting any cheaper.
Macnica Americas has a raffle for a DE10-Nano board on their LinkedIn page. Might be worth checking out if you want to try to get one for free.
Post Reply