User Port Extender / SD Card Reader Interface

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JasonStonier
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Re: User Port Extender / SD Card Reader Interface

Post by JasonStonier »

Wheel_nut wrote:
Mon Oct 26, 2020 2:47 am
Now I hadn't seen JasonStonier's design - I must have blinked! If you decide not to proceed, I will buy some of his boards though they don't solve the stand-off support issue.
Mine's super simple - I'm finishing it up today and was intending to order the boards on the slow boat tonight. Happy to make any changes people think would be of value. I'll post a picture when I'm done. As this needs a mod to the printer port, one thing I really want in my design is to include a header to allow one to use grabber clips rather than soldering direct to the motherboard for the MOSO and VCC.

I don't think there's any harm in having multiple options - mine, I'm doing basically for myself and if other people want one then I'll be putting them out at cost price for the community.

What's the "standoff issue"?

Mine mounts the SD board perfectly centrally to the PCB which means the ports either side are -just- still accessible, with the SD board flat to the adapter PCB so there's no flex.

[edited]
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KenLowe
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Re: User Port Extender / SD Card Reader Interface

Post by KenLowe »

Deleted duplicate post
Last edited by KenLowe on Mon Oct 26, 2020 3:00 pm, edited 2 times in total.
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Re: User Port Extender / SD Card Reader Interface

Post by KenLowe »

This is the problem with my user port board. The SIL header is quite slack and allows movement of the board, particularly at the SD card end. I want to use a standoff at the sd card end to prevent it from pivoting so much. My board is a little bit different the one you're designing. The primary purpose of my board is to provide a means of getting 5v from the user port (to power something on the 1MHz bus), whilst something else is plugged into the user port. As an extra, I added a header that allows the MicroSD card adapter to be easily plugged in:
20201026_144738.jpg
20201026_144722.jpg
Last edited by KenLowe on Mon Oct 26, 2020 2:59 pm, edited 1 time in total.
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Re: User Port Extender / SD Card Reader Interface

Post by JasonStonier »

Ok, makes sense. Mine is a pure Printer port adapter and the SD board sits flush to the PCB - prototype layout here:

viewtopic.php?f=8&t=20843
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Re: User Port Extender / SD Card Reader Interface

Post by KenLowe »

JasonStonier wrote:
Mon Oct 26, 2020 2:57 pm
Ok, makes sense. Mine is a pure Printer port adapter and the SD board sits flush to the PCB - prototype layout here:

viewtopic.php?f=8&t=20843
Yup, I provided a link to your thread in an earlier post:
KenLowe wrote:
Mon Oct 26, 2020 1:29 am
The easiest solution is to just build a dedicated printer port adaptor, like this: viewtopic.php?f=8&t=20843.
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Re: User Port Extender / SD Card Reader Interface

Post by JasonStonier »

Yeah, thanks - I wanted to make it clear it was a prototype, not a final design :D

[edit]

We're trying to do very different and, I think, nicely complimentary things. I certainly don't want to tread on your toes :wink:
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Re: User Port Extender / SD Card Reader Interface

Post by KenLowe »

Wheel_nut wrote:
Mon Oct 26, 2020 1:43 pm
In studying your Layout, it just struck me that the 10mm setback is only required on the USER Port side in order to accommodate the standoff pin on that side. The MicroSD Card could overhang the clips on the Printer Port Port side as does on your current design. Thus, the width of the Board could be reduced by 10mm to 34mm which may still fit in the Master with only one Header fitted. This would be my definite preference!

This would definitely work for the Beeb but I can't verify it for the Master. See the sketch below. I have overlaid the MicroSD Card in Red and I believe that you said earlier that the maximum width available on the Master is 37mm so it is a tight squeeze and would only fit on the Master with ONE Header fitted.
Maximum depth available for the Master is about 27mm (28, possibly even 29 at a push), not 37mm! So I don't have the 10mm of free space that you're showing where the 2 x 10 row of pins are located. If you have a look at the board layout I posted earlier, you'll see that at best I've got about 1mm, which could possibly become 2 or 3 if I push the board dimensions.

Edit: And here's a 3D render of the board with the little dead leg:
Universal MicroSD Card Adaptor 4.PNG
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Re: User Port Extender / SD Card Reader Interface

Post by Wheel_nut »

KenLowe wrote:
Mon Oct 26, 2020 3:22 pm
Maximum depth available for the Master is about 27mm (28, possibly even 29 at a push), not 37mm! So I don't have the 10mm of free space that you're showing where the 2 x 10 row of pins are located. If you have a look at the board layout I posted earlier, you'll see that at best I've got about 1mm, which could possibly become 2 or 3 if I push the board dimensions.

Edit: And here's a 3D render of the board with the little dead leg:
Universal MicroSD Card Adaptor 4.PNG
OK, that's an excellent squeeze of a quart into a pint pot!.

Let me know what the price breaks are on order quantities from the Fabricator and I would like to by a "bunch" of the Boards. I am happy to build them and send them back to you if you intend to hold a stock.

Thank you very much for indulging me with your time and intellect in this and my Gotek Utilities needs.

Robin
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Re: User Port Extender / SD Card Reader Interface

Post by Wheel_nut »

KenLowe wrote:
Sat Oct 24, 2020 11:44 pm
Those stand-offs look ideal. I'm only proposing to use a single standoff. I don't want the board to start clashing with the IDC lugs on the beeb connector. This is roughly what it would look like. Hopefully I've got the mounting hole in the right position! I'm going to be placing an order shortly for some other boards, so I'll get a small batch of these made up at the same time and see how they come out.
Ken, Don't order those Nylon Stand-Offs that I linked earlier. I have found an identical product in quantities of 50 at a more reasonable price. I will place an order once I have Board Order quantities and will share with you.

Robin
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Re: User Port Extender / SD Card Reader Interface

Post by KenLowe »

Right, here's the latest 'Universal' board layout. Please check that the routing looks correct:
Universal board layout
Universal board layout
...and with MicroSD card reader overlay
...and with MicroSD card reader overlay
...and with dimensions
...and with dimensions
I've checked the dimensions against the Master, and it should just about work. However, the printer port lugs will need to be in the closed position to make space for the standoff, if you're using the universal board in the User port slot. That means you will need to have your printer port device connected before you insert the universal board. Similarly, if you want to remove a device from the printer port, you will need to remove the universal board first to allow the printer port lugs to be opened to release the printer port cable / device:
Universal adaptor plugged into beeb
Universal adaptor plugged into beeb
Universal adaptor plugged into beeb - lugs closed
Universal adaptor plugged into beeb - lugs closed
Universal adaptor plugged into beeb - lugs open
Universal adaptor plugged into beeb - lugs open
Last edited by KenLowe on Mon Oct 26, 2020 11:27 pm, edited 1 time in total.
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Re: User Port Extender / SD Card Reader Interface

Post by Wheel_nut »

KenLowe wrote:
Mon Oct 26, 2020 10:39 pm
Right, here's the latest 'Universal' board layout. Please check that the routing looks correct:
Very good pictures and I have traced and checked that the wiring is correct. Lots of Ground paths - Good. Vcc is a single track and care needs to be taken not to draw excessive current from the Power take-off as there is no current limiter.
I've checked the dimensions against the Master, and it should just about work. However, the printer port lugs will need to be in the closed position to make space for the standoff, if you're using the universal board in the User port slot. That means you will need to have your printer port device connected before you insert the universal board. Similarly, if you want to remove a device from the printer port, you will need to remove the universal board first to allow the printer port lugs to be opened to release the printer port cable / device:
The annotation to your pictures is not quie right but I have figured it out ...

I don't think that is much of a hardship considering the amount of function that is being packed into the space that was only intended to house some Flat Cable connectors!.

All looks good to me and I would be delighted to send to the Fab.

I await the Order quantity price breaks and will then press the button to order Headers and the stand-offs on the Slow Boat.

This is getting exciting! ... Robin
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Re: User Port Extender / SD Card Reader Interface

Post by KenLowe »

Wheel_nut wrote:
Mon Oct 26, 2020 11:11 pm
Very good pictures and I have traced and checked that the wiring is correct. Lots of Ground paths - Good. Vcc is a single track and care needs to be taken not to draw excessive current from the Power take-off as there is no current limiter.
There is actually a full ground pour on both sides of the board. Regarding the Vcc, the limiting factor may actually be the wire used to connect Vcc to pin 26 inside the beeb / master, but yes, the power pass through connector is not meant to power another beeb!
Wheel_nut wrote:
Mon Oct 26, 2020 11:11 pm
The annotation to your pictures is not quie right but I have figured it out ...
Sorted... and your spelling of 'quite' was not quite right either, but I've figured that out :lol: :lol: :lol:.
Wheel_nut wrote:
Mon Oct 26, 2020 11:11 pm
I await the Order quantity price breaks and will then press the button to order Headers and the stand-offs on the Slow Boat.
I sent you a PM earlier with a link to the gerber files. You should be able to use that to check prices and order the boards yourself.
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Re: User Port Extender / SD Card Reader Interface

Post by Wheel_nut »

KenLowe wrote:
Mon Oct 26, 2020 11:28 pm
Wheel_nut wrote:
Mon Oct 26, 2020 11:11 pm
Very good pictures and I have traced and checked that the wiring is correct. Lots of Ground paths - Good. Vcc is a single track and care needs to be taken not to draw excessive current from the Power take-off as there is no current limiter.
There is actually a full ground pour on both sides of the board. Regarding the Vcc, the limiting factor may actually be the wire used to connect Vcc to pin 26 inside the beeb / master, but yes, the power pass through connector is not meant to power another beeb!
Oh! I did wonder ... Whereas it is not easy to limit the current drawn from the User Port, I am going to add a 1A self resetting Polyfuse on the Wire add supplying Vcc to Pin 26 of the Printer Port. I have about a foot length of Radial Inserter Taped Polyfuses from a distant past life!
Wheel_nut wrote:
Mon Oct 26, 2020 11:11 pm
The annotation to your pictures is not quie right but I have figured it out ...
Sorted... and your spelling of 'quite' was not quite right either, but I've figured that out :lol: :lol: :lol:.
Touche!
Wheel_nut wrote:
Mon Oct 26, 2020 11:11 pm
I await the Order quantity price breaks and will then press the button to order Headers and the stand-offs on the Slow Boat.
I sent you a PM earlier with a link to the gerber files. You should be able to use that to check prices and order the boards yourself.
Got it. Have placed the Order and have replied to your PM.

Robin
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Re: User Port Extender / SD Card Reader Interface

Post by KenLowe »

Received a couple of PCBs from Wheel_Nut today, so I've soldered on the headers to see how well it fits. It's been mentioned before, but to reiterate, if you're wanting to use this board in a Master, you can only solder on one of the headers as there not enough room in the well for both. Here's a couple of photographs showing the board plugged into the user port and the printer port. You can see that there is just about enough space between the connector lugs to insert a standoff that will hold the MicroSD card adaptor board more securely in position:
Printer Port
Printer Port
User Port
User Port
With MicroSD card reader plugged in
With MicroSD card reader plugged in
And this is them plugged into the beeb. In this case I could have soldered on the other header which would allow the one board to be used in either User or Printer port by just turning it around:
User and printer port
User and printer port
With MicroSD card reader plugged in
With MicroSD card reader plugged in
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Re: User Port Extender / SD Card Reader Interface

Post by Wheel_nut »

My Parts arrived this morning and I have built up a few boards with BOTH Headers fitted as I only have Beebs and no Master. Here are some pictures of the finished product with the support stand-off pillar fitted.

These are the de-constructed Board components:
20201114_130813.jpg

... and fitted to the Printer Port:
20201114_131226.jpg
... and fitted to the User Port:
20201114_131007.jpg
Well Done and thank you KenLowe =D> =D> :)

Robin
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Re: User Port Extender / SD Card Reader Interface

Post by KenLowe »

Nice one. I'm still waiting for my standoffs to arrive. Hopefully won't be too far away.

The million dollar question, thought...

Do they actually work in both the User and Printer ports???
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Re: User Port Extender / SD Card Reader Interface

Post by Wheel_nut »

KenLowe wrote:
Sat Nov 14, 2020 3:32 pm
Nice one. I'm still waiting for my standoffs to arrive. Hopefully won't be too far away.

The million dollar question, thought...

Do they actually work in both the User and Printer ports???
Of Course they do! They wre designed by the SilverBack! ... and Clyde Built. :lol:
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Re: User Port Extender / SD Card Reader Interface

Post by JasonStonier »

British engineering at its best! Very neat solution. Nice work, chaps.

(has the SilverBack moniker stuck now, Ken? If I've contributed one thing to this community, I'm glad it's that)
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Re: User Port Extender / SD Card Reader Interface

Post by KenLowe »

Wheel_nut wrote:
Sat Nov 14, 2020 3:46 pm
Of Course they do! They wre designed by the SilverBack! ... and Clyde Built. :lol:
Well, there's a recipe for disaster, then :lol:.
JasonStonier wrote:
Sat Nov 14, 2020 3:51 pm
(has the SilverBack moniker stuck now, Ken? If I've contributed one thing to this community, I'm glad it's that)
I sure as hell hope not :shock:.
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Re: User Port Extender / SD Card Reader Interface

Post by KenLowe »

Here's Rev 2 of my user port extender, with the extra mounting holes to secure the MicroSD card adaptor if you want to use user port for MicroSD card based floppy drive. With the use of a couple of stand off pillars, the MicroSD adaptor is now held securely in place. Many thanks to Wheel_nut for posting a few of these pillars to me for testing.

As with the original user port extender, the primary purpose of this board is to provide a power pass through feature from the user port, whilst still being able to connect a cable to the user port for it's original intended purpose. The ability to directly connect a MicroSD card adaptor was a secondary benefit.

As before, it is important to stress that if you want to use the MicroSD card adaptor with this user port extender, then you shouldn't try plugging an additional user port device into the extension connector at the same time. That would be the same as trying to plug two devices into the user port at the same time!

Also, this board is not to be confused with the 'Universal' MicroSD adaptor board that I designed for Wheel-nut. The purpose of that board is solely to interface a MicroSD card adaptor to either the User port or the Printer port using the same adaptor board. That board does NOT have any User port pass through capability.

Here's a photo showing the User port extender without the MicroSD adaptor plugged in. Note that the cut out notch in the PCB is so that the board can clear the securing lugs on the User port connector:
User port extender. Can you spot the stupid silk screen error???
User port extender. Can you spot the stupid silk screen error???
and here's a couple of photos showing the User port extender with the MicroSD adaptor plugged in, and the pass through power cable connected:
User port extender with MicroSD card adaptor plugged in
User port extender with MicroSD card adaptor plugged in
...and the underside of the User port extender
...and the underside of the User port extender
and here's a couple of photos showing the board plugged into the Master. I've shown it with a printer cable plugged into the printer port, and PiTubeDirect and Pi1MHz plugged into the Tube port and 1MHz port respectively to show how everything can be plugged in at the same time:
Master: Close up of User port extender with MicroSD card adaptor plugged in plus a cable connected to the printer port
Master: Close up of User port extender with MicroSD card adaptor plugged in plus a cable connected to the printer port
Master:...and also with a couple of PiZeros for TubePiZero and PI1MHz
Master:...and also with a couple of PiZeros for TubePiZero and PI1MHz
And finally, the same on the beeb. There's much more space under the beeb than there is in the Master:
Beeb: Close up of User port extender with MicroSD card adaptor plugged in plus a cable connected to the printer port
Beeb: Close up of User port extender with MicroSD card adaptor plugged in plus a cable connected to the printer port
Beeb:...and also with a couple of PiZeros for TubePiZero and PI1MHz
Beeb:...and also with a couple of PiZeros for TubePiZero and PI1MHz
Last edited by KenLowe on Thu Nov 19, 2020 10:22 pm, edited 2 times in total.
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Re: User Port Extender / SD Card Reader Interface

Post by KenLowe »

Oh, and for those who purchased an original Rev 1 board from me, I'd be willing to provide you with a free upgrade to this Rev 2 board if you're happy to cover the postage costs.

However, please note that the MicroSD adaptor connector pins on the board have also been transposed so a standard MicroSD adaptor board can be plugged in by just straightening out the 90 Deg header pins. It's no longer necessary to remove the header and solder onto the opposite side of the MicroSD adaptor board. If you've done that for the Rev 1 board, then you'd need to reverse that for this Rev 2 board.
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Re: User Port Extender / SD Card Reader Interface

Post by Wheel_nut »

Beautiful piece of design. You probably have an order of magnitude more processing power in the Connector Well than there was in the System/360 Model 65 that was re-packaged to fit in the Cone of the Apollo Capsule! =D> =D>
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