picaxe firmware in a different package

edmunds

Senior Member
Dear all,

Is there any evidence of picaxe firmware being compiled into other versions of PIC18L45K22 packages available? Like UQFN 44-pin, for an example? Would this be something that one could do, given the right tools? Or is it up to RevEd to release something like this as a new product? If the latter, can I register a wish, please? :)

With PCB production becoming available to hobbyists and reflow soldering "at home" process cheap and thoroughly described in thousands of tutorials and videos online, these smaller packages become more and more interesting for greater number of hobbyists around the World. Most of us will never hit the ceiling of picaxe technical limitations if compared to bare MCUs and most of us cannot spare the time to learn the whole deal of C or assembler programming for our hobby. But we want to build small things in tight spaces :).

Thank you for your time,

Edmunds
 

Goeytex

Senior Member
You can get a Picaxe 40X2 in UQFN format from the Picaxe Store.

The Picaxe Firmware is not available to end users and there are no tools to allow flashing a PIC with Picaxe Firmware. We are at the mercy of Rev Ed as to what is available and in what format.
 

edmunds

Senior Member
You can get a Picaxe 40X2 in UQFN format from the Picaxe Store.

The Picaxe Firmware is not available to end users and there are no tools to allow flashing a PIC with Picaxe Firmware. We are at the mercy of Rev Ed as to what is available and in what format.
I think it is TQFP package. And UQFN would be smaller. Not by much one might say 10x10 to 8x8, but it is still real estate. And real estate is expensive :).

Thank you for your reply,

Edmunds
 

Goeytex

Senior Member
I am looking at the PIC Datasheet and the TQFP package seems to be a 44 Pin device. Per the same PIC datasheet the 40 Pin is UQFN. It would be nice if the folks at Rev Ed would do us the courtesy of telling us what package the SMD 40X2 comes in.

Edit: It seems the photo at the Picaxe Store is of a 44 Pin TQFP device and not a 40 Pin. So it may indeed be TQFP. The extra 4 pins are not used anyway and are labeled "NC".

What's up with micro-sizing everything? Are you doing commercial stuff or just somewhat obsessed with really small things? Small is not necessarily better, especially for most hobbyists and us old folks who can't see without a magnifier.

As far as my personal projects go, I couldn't care less about 5 mm of board space. Only if a client demands micro-sizing do I worry about space and then I generally ( but not always) use something other than Picaxe.
 
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Technical

Technical Support
Staff member
I am looking at the PIC Datasheet and the TQFP package seems to be a 44 Pin device. Per the same PIC datasheet the 40 Pin is UQFN. It would be nice if the folks at Rev Ed would do us the courtesy of telling us what package the SMD 40X2 comes in.
Edit: It seems the photo at the Picaxe Store is of a 44 Pin TQFP device and not a 40 Pin. So it may indeed be TQFP.
Please see here (at bottom) for a full listing of all standard stock part sizes:

http://www.picaxe.com/What-is-PICAXE/PICAXE-Chip-Sizes/

Any size is available to special order, we do use smaller on some products e.g. 28X2 on AXE201. However minimum quantities would normally apply to special batches.
 

srnet

Senior Member
And real estate is expensive
Smaller SMT parts require PCBs that use finer tracks and smaller vias, these PCBs will be more expensive.

Using smaller SMT parts will not only make DIY assembly harder but could well be more expensive too, as the PCBs cost more.
 

bpowell

Senior Member
What's up with micro-sizing everything? Are you doing commercial stuff or just somewhat obsessed with really small things? Small is not necessarily better, especially for most hobbyists and us old folks who can't see without a magnifier.
I just dipped my toe into SMT work...I find it a ton of fun. And I was able to fit all the functionality (plus some "future proofing") onto a board with SMT that I may not have been able to with through-hole.

Attached is the "Port expander" board I made...It started as a binary clock...but, I figured if I was going to have PCBs made, they should be multi-purpose...so I added a few components. I have 2 MCP23017 IO expanders, an EEPROM, a RTC, and a PICAXE 08M2 on the front...and I made a spot for a 20X2 on the back, with "break out" pads to add components as necessary to make use of the 20X2.

I'm still using my proto-board version of this circuit (through hole and DIP components) at my desk at work...but I plan to build another clock or two with these PCBs...in fact, I did build one up...it's in the cupboard keeping time with the battery as I type!

The SMT soldering was a little challenging...but I used 1206 size components, which is about my limit of comfort.

Over all, I think it was a great learning experience...I may do more SMT work later...I just wish I could buy SMT PICAXE here in the states w/out paying the shipping from the UK.

Port Expander Back.pngPort Expander Front.png
 

edmunds

Senior Member
I am looking at the PIC Datasheet and the TQFP package seems to be a 44 Pin device. Per the same PIC datasheet the 40 Pin is UQFN. It would be nice if the folks at Rev Ed would do us the courtesy of telling us what package the SMD 40X2 comes in.

Edit: It seems the photo at the Picaxe Store is of a 44 Pin TQFP device and not a 40 Pin. So it may indeed be TQFP. The extra 4 pins are not used anyway and are labeled "NC".

What's up with micro-sizing everything? Are you doing commercial stuff or just somewhat obsessed with really small things? Small is not necessarily better, especially for most hobbyists and us old folks who can't see without a magnifier.

As far as my personal projects go, I couldn't care less about 5 mm of board space. Only if a client demands micro-sizing do I worry about space and then I generally ( but not always) use something other than Picaxe.
It could become commercial one day, but many things I'm creating are to fit into HO scale (1:87) models of one thing or another. Digital HO scale cars are a prime problem for smaller size. Trucks and buses can be done with what is available. It is also generally cheaper to do thinner traces than smaller boards. So for anything you need more than one board for, it would make sense. I expect to run 200-300 vehicles with digital decoders in the next 2-3 years, for an example. Buying the necessary decoders will cost me between 10.000-15.000eur. I feel I can build them myself with what I know about PICAXE, but chip size is a deal-breaker. Up until now.


Thank you for your time,

Edmunds
 

rq3

Senior Member
Smaller SMT parts require PCBs that use finer tracks and smaller vias, these PCBs will be more expensive.

Using smaller SMT parts will not only make DIY assembly harder but could well be more expensive too, as the PCBs cost more.
Not true, unless they're REALLY small. PCB fab today generally includes traces and spaces down to 6 mils (0.006 inch). Anything finer than that, and features like blind or tented vias, will cost more. Otherwise there's no difference.

Rip
 

srnet

Senior Member
Not true, unless they're REALLY small. PCB fab today generally includes traces and spaces down to 6 mils (0.006 inch). Anything finer than that, and features like blind or tented vias, will cost more. Otherwise there's no difference.
Rip
Smaller SMT devices (a package smaller than the TQFP for 40X2 for instance) will require you to use finer than 6mill traces with smaller than 0.3mm vias, which is the limit of cheap double sided PCBs. The problem is not so much the size of the SMT device itself, but the space required to route all the traces.

There may well be other compelling reasons for wanting to use smaller SMT devices, but cost of PCB real estate is probably not one of them.
 

Hemi345

Senior Member
bpowell:274624 said:
And I was able to fit all the functionality (plus some "future proofing") onto a board with SMT that I may not have been able to with through-hole.
[...]
I just wish I could buy SMT PICAXE here in the states w/out paying the shipping from the UK.
I agree with all of this.
 
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