The Amicus boards are back!

[CPR]

Hi,
All fitted exactly as the photo on the shop.

Bob

Bob, thanks for the reply - but - what I'm asking is - does John fit the headers himself or are they supplied (from the pcb manufacturer) with the headers already fitted?

[RGV250]

Hi,
Looking at mine I would say it is all done by the manufacturer as they are all identical and look too perfect to be done by hand.

Bob

[John Lawton]

Lol, Bob is right, the boards are as supplied by the professional assembler. I just add the handbags and test before despatching.

Why did you ask, Chris, did you want a board without the headers, sorry I don't have any atm.

By the way I've despatched your Amicus 8.

John

[John Lawton]

I wonder how accurate the internal clock is IE for CAN if I ever get round to it again.
Just a small suggestion for future, I wonder if it would be an idea to put tracks on the SSOP adaptor so you could add an external crystal/caps if need be.
Also on the adaptor, is there clearance or will it interfere with shields on top of it?

Sorry I can't answer the question about the clock.

The adaptor is very tight when fitting a shield, but it depends on the pin length of the shield used. I could supply the SSOP adaptor board without pins fitted, so the buyer could solder in plain pins i.e. without the plastic spacer which would save some height.

John

[CPR]

Lol, Bob is right, the boards are as supplied by the professional assembler. I just add the handbags and test before despatching.

Why did you ask, Chris, did you want a board without the headers, sorry I don't have any atm.

By the way I've despatched your Amicus 8.

John

Hi John, Yes! A board without the headers would be especially useful. When/if you have some back in stock (without headers) perhaps you could let me know? Looking forward to receiving the board. Thanks for letting me know!

[John Lawton]

It might be some time before I get more batches of boards made depending on demand. The existing headers could be removed given care and skill.

I would like to fit taller headers than the ones I used, but I haven't found a source for them as yet.

John

[John Lawton]

I wonder if it would be an idea to put tracks on the SSOP adaptor so you could add an external crystal/caps if need be.

Sorry, forgot to answer that question. I hadn't thought about adding a crystal+caps, it might be possible but unless fitted to the underside would add to the height. I had thought of adding pads for decoupling capacitors but I'll await user feedback.

John

[RGV250]

Hi John,
https://www.toby.co.uk/board-to-board-pcb-connectors/254mm-sockets/esq-samtec-254mm-elevated-single-row-socket-strip-2.29mm-contact-11.05mm-profile-12/
Not cheap though.

As for the decoupling caps, would they not cause a problem with the ones on the main board?

Bob

[John Lawton]

Thanks, but at over £5 more per board, way over the top. I can get my present ones, which are 8.5mm high, for a total of £0.77 per board so that's for all of them.

The search continues...

I can't see an issue with additional decoupling caps on the adaptor board which might help keep noise down, it depends on the application, e.g. low level ADC.

John

[trastikata]

https://www.aliexpress.com/item/1005005767805881.html

But you need to buy the spacers separately. Not suitable for mass production though.

[RGV250]

Hi John,
I have noticed a couple of things on the 16A schematic which I think are probably from an earlier design.
You have "optional" for R3 where the wording is not on the 16B schematic. This is also on the Amicus8 schematic.
It says PIC U4 = xxx where it should be U5.

Question, why U4B for the LED, was this just that it was spare otherwise? as most other boards have just the resistor.

Bob

[John Lawton]

Hi Bob,

I'm glad you spotted the deliberate errors 

Yes, I think I renumbered the parts at some point and didn't update the note about the PIC. I forgot to remove the note about R3 (which is fitted). As a dual op-amp is hardly more expensive than a single one I decided to use the spare as a high impedance driver on RB15/RB7 as I think it's sometimes nice to have a built-in flashing light on the board as a sort of 'Hello World' so at least you can know the PIC is working with just a bit of simple code to toggle the port.

John

[trastikata]

I decided to use the spare as a high impedance driver on RB15/RB7 as I think it's sometimes nice to have a built-in flashing light on the board as a sort of 'Hello World' so at least you can know the PIC is working with just a bit of simple code to toggle the port.

Hi John,

indeed a simple LED is very useful. I've been using it to check crystal settings when set to blink with period of 1s, more often as conditional jump indicator, and just as code execution indicator to see if something happens where it is supposed to happen.

The LED is actually a basic debugging and diagnostic tool for me 

[John Lawton]

The adaptor is very tight when fitting a shield, but it depends on the pin length of the shield used. I could supply the SSOP adaptor board without pins fitted, so the buyer could solder in plain pins i.e. without the plastic spacer which would save some height.

Here is an image of the adaptor board underside. The thin gold plated pins have a plastic moulding and together with the pin shoulder that is overall 4.25mm above the pcb. Fitting individual pins without any plastic moulding could reduce the height of the installed adaptor board.

For that reason I could supply the adaptor boards as bare boards if there is a demand?



John

[top204]

Many thanks for the Amicus boards John.

They are beautiful, and it is so lovely to see my "Amicus" idea carried on with such professionalism.

By the way, for anyone who does not know what "Amicus" means. It is an ancient Latin name for a helper or friend or assistant etc...

Is there any documentation for the Amicus boards yet?

[John Lawton]

Hi Les,

glad you like them!

Regarding documentation, see this page but of course there could be more!

Everyone, please let me know on here what you think is needed in addition to the schematic & compatibility info I've provided.

John

[top204]

One thing I would suggest John, is to make the 8 and 16 boards different colours so they do not get mixed up and blow something because of the different pinouts of 8-bit and 16-bit devices. Or make a, new to PICs, user think something is wrong with their code or programmer etc...

That was why I originally made the Amicus18 board 'dark blue' and the Amicus24 board 'red'.