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Old 27th Mar 2023, 4:37 pm   #201
ScottishColin
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Default Re: Yet another MK14 tape interface (ESP32).

I did.

Colin.

Quote:
Originally Posted by SiriusHardware View Post
Did you get a 'Grove' connector with the M5 which breaks out the GND, 5V and two I/O pins from the M5 on a four-way male pin connector?
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Old 27th Mar 2023, 4:40 pm   #202
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Default Re: Yet another MK14 tape interface (ESP32).

I'm trying to have a setup so that nothing is soldered to any other device - this looks like I'd need wires to the main PCB or Realview - is that right?

I'm thinking of something like this (but obviously it needs a finger for the Realview to connect to).

https://kitronik.co.uk/products/5601...obit-pre-built

Colin.

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Originally Posted by Silvester View Post
Re: M5 StickC Plus, You can get suitable proto boards:

https://thepihut.com/products/m5stickc-proto-hat
https://thepihut.com/products/new-mini-proto-unit

The first is probably the best to use because the Grove connection for 5V is OUT (so not suitable to link to MK14 5V). The other connector allows 5V IN (to preserve/charge battery). The only hitch is that the output pins will need to be changed (G32/33 on Grove, G25/26/0 on 8 pin).
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Old 27th Mar 2023, 6:08 pm   #203
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Default Re: Yet another MK14 tape interface (ESP32).

Quote:
Re: M5 StickC Plus, You can get suitable proto boards:
I think Colin's question is more in the order of how best to make a disconnectable connection to Realview at the Realview end.

To be honest I hadn't actually noticed that Realview does not break out the flags and sense inputs and so on on a pin row connector or similar. One for rev 1.1, if there ever is one perhaps.

Silvester's info about the +5V connection runs counter to the connections suggested by Coolsnaz2 as his arrangement does have the +5V wired to MK14 5V, so I think we need a show of hands, or I will have to read up on this myself.

I would suggest soldering IDC twin row male connectors like these :-

https://www.amazon.co.uk/Sourcingmap.../dp/B07DJYFGHX

...on the back of the Realview - the two rows on this connector will fit 'inside' the two more widely spaced soldered pins of the edge connector but you should be able to solder them one to one so that all of the connections from the issue VI are carried onwards to the rear. The ones shown are 40 x 2 way and they only need to be 32 x 2 way but they have a snap-off feature where you can break as many as you want (or don't want) off. This was just the first example I found, other websites may have similar items for less.

To go with this the simplest transition would be a 'Grove to Dupont converter cable'

https://www.aliexpress.com/item/1005002904971236.html

Again, just the first one I found, and no implied recommendation of that particular source. Note the connectors on the ends are Dupont Females which is what you want if you have put male pin row connectors on RealView - they are also available with Dupont male plugs on the end so if you go this route be careful to get the one you intend to.

Edit: Cross posted with Colin.
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Old 27th Mar 2023, 6:18 pm   #204
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Default Re: Yet another MK14 tape interface (ESP32).

Hmm, just noticed that there is a resistor tagged between the rows on the 'track' side of Realview, it would get in the way of a narrow double row connector at that end. You could still solder two single row 32-way connectors to the 32 pins of each row of the edge connector but that would not be as strong and could easily be broken off.
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Old 27th Mar 2023, 6:21 pm   #205
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Default Re: Yet another MK14 tape interface (ESP32).

Unless I'm missing something, I can't see how I can easily solder the IDC connectors to the back of Realview (see photo).

Colin.
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Old 27th Mar 2023, 6:30 pm   #206
SiriusHardware
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Default Re: Yet another MK14 tape interface (ESP32).

Solder the 'short' pins of the IDC pin row connector to the 'bumps' which are the ends of the edge connector's pins, leaving the 'long' pins of the IDC connector pointing straight up in your view in the previous post.

As I said though the tacked-on resistor would get in the way of the double row connector I linked to, so it would have to be two single row connectors mounted / soldered directly on top of the 'bumps' of the edge connector.

Either that or a 32 x 2 row connector with longer pins so you could crank them outwards to land on the solder 'bumps' of the edge connector.
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Old 27th Mar 2023, 6:32 pm   #207
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Default Re: Yet another MK14 tape interface (ESP32).

In reality you only need four, possibly only three pins soldered to the connections for 0V, Sense-B and SIN, (and maybe +5V) but a single pin soldered to a single pad on the exposed side of the PCB would soon get knocked off.

Last edited by SiriusHardware; 27th Mar 2023 at 6:40 pm.
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Old 27th Mar 2023, 7:19 pm   #208
ScottishColin
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Default Re: Yet another MK14 tape interface (ESP32).

I'm really not confident in my ability to solder to the 'bumps' - I'll take another look.

Colin.
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Old 27th Mar 2023, 8:00 pm   #209
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Default Re: Yet another MK14 tape interface (ESP32).

In the meantime I still have not managed to find the definitive answer to the question, is it OK to back-power the M5stickCPlus through the 5V terminal on the Grove connector? There is a precedent for this, genuine Arduinos can both supply +5V from and be powered via +5V applied to their +5V terminal. According to Slothie some knock-off Arduinos use an inferior power control device which can not tolerate being back powered in the way that the real thing can. However that is Arduino - I am no closer to resolving the same question when it comes to the M5StickCplus.

What does seem clear is that the device core, like on the Raspberry Pi or Pi Pico, is a 3V3 logic device and one thing you probably should not do is to apply 5V Logic-1 signals from an external source directly to the GPIO terminals on the Grove connector. In this application it luckily does not matter as both I/O pins on the Grove connector are used as outputs and are connected to inputs on the MK14.
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Old 27th Mar 2023, 8:22 pm   #210
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Default Re: Yet another MK14 tape interface (ESP32).

Getting closer - something like this but with a PCB connector is what I'm after.

https://www.amazon.co.uk/GeeekPi-Con.../dp/B08C4S8NPH

Clin.
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Old 27th Mar 2023, 8:35 pm   #211
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Default Re: Yet another MK14 tape interface (ESP32).

OK, M5STickCplus circuit diagram found here:-

https://m5stack.oss-cn-shenzhen.aliy...s_20200616.pdf

Looking at this it can be seen that the line going to '5V' on the grove connector goes to an internal line called 'Ext_VDD' which is unhelpfully ambiguous - does that mean 'VDD for external devices' or does it mean 'VDD from external source'?

However, if we follow the 'Ext_VDD' line to its source we find it coming out of the OUT terminal of the '5Vout_boost' regulator section so on the face of it, applying +5V TO this terminal would usually be a bad idea.

Moving to the data sheet for the 'boost' regulator IC concerned-

http://www.sg-micro.com/uploads/soft...1653990782.pdf

I can not see any specific statement to the effect that this device can tolerate having an offboard 5.0V source applied to its output.

Others may be patient enough to sift through it more slowly.
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Old 27th Mar 2023, 8:48 pm   #212
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Default Re: Yet another MK14 tape interface (ESP32).

It looks like the resistor and wire mod could both be moved outside the footprint of the connector.

Those square header pins and matching female header sockets are also available in three rows. The two outside rows are on 0.2” spacing from each other which I think matches the back of the edge connector on realview. Its quite easy to remove the centre row of pins on ether the male or female connector by pulling on the pin with long nose pliers. The female header socket would be the best choice to avoid accidental shorts and accept the square pin terminated dupont jumper cables.

Last edited by Mark1960; 27th Mar 2023 at 8:50 pm. Reason: Spelling again
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Old 27th Mar 2023, 9:01 pm   #213
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Default Re: Yet another MK14 tape interface (ESP32).

This type might be easier.
https://www.aliexpress.com/item/1005004256489714.html

This is the three row type.
https://www.aliexpress.com/item/32892991039.html

I’ve not tried these suppliers, just adding links as example of the types of connector. They can be cut down to smaller length with a little care and a sharp knife to trim the ends.
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Old 27th Mar 2023, 9:03 pm   #214
SiriusHardware
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Default Re: Yet another MK14 tape interface (ESP32).

Do you have links to examples of the female three row connectors? I could not find any through hole 32 x 32 way female twin row connectors. Certainly it would be better for the ones coming out the back of Realview to be female, I just couldn't see any.

A three row female DIN 41612 connector perhaps, with only rows A and C fitted, pins soldered onto the 'bumps' of the edge connector pins - although Colin may still not like that idea.

There is also the problem (mentioned above) that the +5V terminal on the grove connector on the M5 module seems to be an output so having four bare pins on the ends of flying leads dangling off the M5 module may also pose a potential problem.

Edit: Crossed with Mark.
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Old 27th Mar 2023, 9:11 pm   #215
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Default Re: Yet another MK14 tape interface (ESP32).

Had a quick look, Mark, I'm not sure but the first ones you linked to, although they look ideal for soldering on top of the stunted ends of the edge connector pins - I think they may only be 1mm pitch spacing so incredibly tiny, far smaller than needed.

The ones in your second link look more promising - certainly the right pitch - if, as you say, you were to extract the middle row of pins, but there again we are back to male pins. This appears to be a very male dominated sphere, for some reason.
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Old 27th Mar 2023, 9:15 pm   #216
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Default Re: Yet another MK14 tape interface (ESP32).

Quote:
Getting closer - something like this but with a PCB connector is what I'm after.
We can visualise exactly what you need but there is virtually zero chance of finding that item already on the market because, unfortunately, we ourselves have only just invented the need for it.

The most likely way for those to become available would be if either Realtime or Mr. Oddy (or Slothie perhaps) could knock one up in Kicad or whatever everyone prefers to use.
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Old 27th Mar 2023, 10:03 pm   #217
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Default Re: Yet another MK14 tape interface (ESP32).

How about these - three-row DIN 41612 female connector with only the outer rows populated, and not even too badly priced.

https://uk.rs-online.com/web/p/din-4...ectors/5083101

This would still, to Colin's undoubted dismay, have to be soldered to the stumps of the pins of the edge connector.

Matching plug-in male connectors (to the rear pins of which you would solder the wires from the M5 stick or just push them on if they were dupont female) - every single matching one that comes up for me has right angled pins. Solution: Bend the pins straight and cut them all to the same neat length.

An example:

https://uk.rs-online.com/web/p/din-4...ectors/0251172

Both connectors linked to are the same 'type', type C, and should mate OK, the only thing I'm not sure of is the 'Class' rating - if it relates to the temperature or maximum voltage or amps rating that's probably not important here.

As always you can probably find these items cheaper if you Google the manufacturer's part number stated in the RS listing,

Last edited by SiriusHardware; 27th Mar 2023 at 10:11 pm.
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Old 27th Mar 2023, 10:36 pm   #218
ScottishColin
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Default Re: Yet another MK14 tape interface (ESP32).

If anyone ever did happen to take up this challenge, I'm more than happy to get some made and sent out to those who wanted one.

Edit: it would be useful (unless I've mis understood) to have 5v bought out on any new connector too.

Colin.

Quote:
Originally Posted by SiriusHardware View Post
Quote:
Getting closer - something like this but with a PCB connector is what I'm after.
We can visualise exactly what you need but there is virtually zero chance of finding that item already on the market because, unfortunately, we ourselves have only just invented the need for it.

The most likely way for those to become available would be if either Realtime or Mr. Oddy (or Slothie perhaps) could knock one up in Kicad or whatever everyone prefers to use.
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Old 27th Mar 2023, 10:45 pm   #219
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Default Re: Yet another MK14 tape interface (ESP32).

Quote:
Originally Posted by SiriusHardware View Post
Had a quick look, Mark, I'm not sure but the first ones you linked to, although they look ideal for soldering on top of the stunted ends of the edge connector pins - I think they may only be 1mm pitch spacing so incredibly tiny, far smaller than needed.
I was just looking at the pictures, not paying attention to the pitch. Same supplier has the 2.54mm pitch type, but I’m guessing colin might not want 200 Aliexpress is also probably too slow, just using these links as a picture of what’s available.
https://www.aliexpress.com/item/1005001894708966.html
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Old 27th Mar 2023, 11:29 pm   #220
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Default Re: Yet another MK14 tape interface (ESP32).

Quote:
Originally Posted by SiriusHardware View Post
OK, M5STickCplus circuit diagram found here
>>
>>
Moving to the data sheet for the 'boost' regulator IC concerned-

http://www.sg-micro.com/uploads/soft...1653990782.pdf

I can not see any specific statement to the effect that this device can tolerate having an offboard 5.0V source applied to its output.

Others may be patient enough to sift through it more slowly.
Well being as the SGM6603 Synchronous Boost Converter's datasheet Abs Max Ratings of Vout etc are all referenced to Gnd (rather than Vin), then in theory it shouldn't be damaged by having a voltage on its output, without having one present on its input.
So could probably try it, to see what happens, as shouldn't damage it at least - But whether it would actually like operating in practice is another matter, and not really covered by the specified recommended operating conditions
(quite common that datasheets from the more obscure far-east manufacturers aren't too comprehensive, although this one is better than many I've seen).

With linear-regs, it's often a good idea to fit a diode from output to input, to protect against Vout>Vin, which is apparently a way of damaging many like 7805's etc. But may not be able to do this on a Boost converter, where Vout is usually > Vin
- Although if Vin to the module is rated to 5V (as Vcc to SGM6603 is), then may be able to actually join the two together, if nothing else is connected to Vin side.

However, looking at the module's schematic, the input to the SGM6603 is fed from 'IPSOUT' on an even-more obscure / complex AXP192 Power Management Unit IC. And not-clear what that voltage is / if there could be some back/parasitic powering into that and its other supply outputs.

Last edited by ortek_service; 27th Mar 2023 at 11:40 pm.
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