You guys are something else! Thanks for all the help. That's great to hear the reg. situation can be simplified.
Back to square one I suppose.
I've got one other question if you don't mind. As for programming the boards, it would cost far more in resources to make a dedicated "ISP programming board". Trying to cut down on my budget and overall costs, couldn't I just add a 2x5 pin shroud to each board and use the USBasp ISP programmer? (Haven't tried out that programmer yet.)
Maybe its just me, but I don't like using the Arduino to program Attinys. Switching out chips back and forth and whatnot.
If swapping out the microcontroller to program it bugs you, there's always the option of putting a 6 pin header on your board and programming them in-place too. If you add a dedicated programming board, are you thinking that would just be a set of headers and some kind of switch to select the target uC to program? If so that sounds like headers on each uC level would be cheaper/simpler to me, but entirely your call of course.
If you have lots of them, why not set up a ZIF socket and ISP circuit on a breadboard?
Then your modules wouldn't need headers either.
Another thing to give you mileage would be to use SPI shift-registers to light the leds and 1 Tiny to send data to many daisy-chained shift registers. A Tiny running at 8 MHz can send SPI data at 1 MBps or less which allows longer SPI bus lines but still you could change 40 8-bit registers 20,000 times a second with cycles to spare for another 6,214... which would give time to communicate with other Tinys on the same SPI bus.
I wouldn't bother with boards for something so simple, there's another buck apiece for many pieces. I like sockets, you can plug leads (headers too?) in the holes as easily as chips and either solder to the legs or push them into connectors. They're cheap and even cheaper in quantity, and a few extra pins don't hurt do they?
strykeroz:
If swapping out the microcontroller to program it bugs you, there's always the option of putting a 6 pin header on your board and programming them in-place too. If you add a dedicated programming board, are you thinking that would just be a set of headers and some kind of switch to select the target uC to program? If so that sounds like headers on each uC level would be cheaper/simpler to me, but entirely your call of course.
Cheers !
Geoff
I know what I said before, but things change as new ideas develop.
Now, I pretty sure I would like all the boards made equal. But they will still have all the functionality as before.
I think that is possible with the USBasp. Cuts down on: costs, overall work, wires and frees up my Arduino. The most practical solution I can see is simply adding a few male pins for the 5x2 native USBasp connection.
To be honest, I'm very unsure. New territory for me. So your input is very much appreciated.
On a side note, one thing I forgot was 10k pull-down required between signals. AH, that is going to be hard to incorporate. Probably have to use a DIP switch.
There is no wrong way in this choice (at least I don't think there is). I'm working on a small board now with ATTiny where I'll have 60 made up - the first 10 prototypes arrived tonight in fact. The programming for this one is unlikely to be often, so I'm going for a socketed ATTiny to cater for those occasions rather than soldering 60 sets of headers. Colour me lazy maybe In contrast, if you think these things will be programmed often I'd do what you're suggesting with the ICSP headers (or equivalent) for sure.
I've seen some designs using bare pads for the ICSP so a rig with pogo pins can be used for programming also.
It's good to see you're taking this one back on. Do keep this thread updated. Cheers !
Geoff
No wrong way sure. But if you ever get into manufacture you may find that market competition provides for product evolution. In this world it's survival of the cheapest in a bang for the buck manner. Function, lifetime, maintenance and running costs all factor into the bang but when the price is higher for less than the same overall increase or the thing will soon enough be obsolete then you've made a Tiger tank when you should have made a dozen T-34's.
Trying to find a good solution for switch between the 5v USBasp ISP and the 5v-15v DC jack. I'm sure I can figure it out but if you have a simple solution I'm all ears.
One thing that is mind numbing, so currently I have a resistor on each I/O going "up" for the pull down. I'm curious if would it would be possible to use just a single resistor for all of them? But being their not all on at the same time, or if they were by chance. I don't know to even where to start with that formula. Maybe I could just calculate for them all to be on, and still get a good pull down result if only one is actually sending.
dritchie0042:
Now, I pretty sure I would like all the boards made equal. But they will still have all the functionality as before.
Just trying to point out that 1 board can run many leds in different ways. 1 board per led is amazingly inefficient in terms of cost, materials and time. It even multiplies the number of chips you have to re-program with all that goes with that. For what you do, you don't really need boards, just something to hold parts together and attach to enclosure or mounting. A lot of things can be built right onto/into cabling.
I can get up to 32-pin narrow IC sockets for 15 cents each, maybe less in quantity.
I get small generic boards with hole pads and finger edges, they run over a buck each in 5 to 10.
dritchie0042:
Now, I pretty sure I would like all the boards made equal. But they will still have all the functionality as before.
Just trying to point out that 1 board can run many leds in different ways. 1 board per led is amazingly inefficient in terms of cost, materials and time. It even multiplies the number of chips you have to re-program with all that goes with that. For what you do, you don't really need boards, just something to hold parts together and attach to enclosure or mounting. A lot of things can be built right onto/into cabling.
I get small generic boards with hole pads and finger edges, they run over a buck each in 5 to 10.
Why would you buy an Arduino to run a single LED? As I explained how this could running LED's, that is isn't the only and intended purpose.
As of now, one Analog pin is connected to the on board LED. But all 5 Attiny85 I/O pins communicates up to the next board, as well as they all go outwards (no pull down) via headers if you wanted to use jumper wires to go out to a breadboard etc.
As for selling these, I only want to sell one or two sets to make my money back so I can throw back towards another project. There are many ways to skin a cat, these will be made on PCB's.
I pray to the pcb layout gods this is the last base board I'll need to design for this project. And I couldn't find a way to make them all equal. Adding being I'm not going to manufacturer these now, I can use what double sided clad I have. Honestly I don't think its possible on single. . .
If it works I will not be making anymore changes. Fingers crossed, I'm going to start putting together the top boards.
(Excuse the bottom right route, I know its touching.)
This is the design for the higher level boards. The 3D models aren't accurate connection wise. LED Pin won't be there but I had to represent them somehow.
In contrast, if you think these things will be programmed often I'd do what you're suggesting with the ICSP headers (or equivalent) for sure.
