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FireGod
06-04-2007, 10:20 PM
I had a thought. A very very small board could be designed to adapt a Renard 16F688 PIC chip to a 595 socket.

Change the parallel port connector to a serial port connector. Then send Renard serial data to all the first PIC chip (just like a 595). The PIC would send the data to the next IC (just like a 595).

A board with perferations could be made so there could be a whole bunch of these little boards in one then snap them a part.

Anyone interested?

Macrosill
06-04-2007, 10:46 PM
Are you saying you can convert a 64 channel 595 board to Renard with very minimal work? If so I would be inclined to do that.

If I am misunderstanding your intent please give me more details.

Brian

P. Short
06-04-2007, 11:07 PM
Is this part of the topic in the 'Other hardware' category?

--

Phil

Macrosill
06-04-2007, 11:13 PM
From my understanding the other topic is about a Renard protocol that would allow the 595 boards to be directly connected to the Renards in a daisychain fashion. This topic is about converting a 595 board to a Renard in and of itself.

That is if I am understanding correctly.

P. Short
06-04-2007, 11:21 PM
Basically the same thing in my mind...the only difference is that in case there is a true renard in between the PC and the adaptor board/chip, and in the other case the PIC is directly connected to the adaptor board chip...so almost the same thing.

--

Phil

P. Short
06-04-2007, 11:25 PM
Oh...I assumed that FG wasn't talking about converting the 595 to dimming, still just allowing the 595 to be daisy-chained a Renard interface...

So I guess that I'm not sure what this topic is about.

--

Phil

FireGod
06-04-2007, 11:29 PM
Here is the board I have in mind. Plug it into a 595 socket, plug in a 16F688 programmed with the Renard protocol, and put only one oscillator on one of the boards (not all of them).

A zero crossing signal will also need to be provided.

http://web.olpdsl.net/firegod/DIY/595conv.JPG

P. Short
06-04-2007, 11:32 PM
So your idea is to 'dim' the 595 by replacing the first chip with a PIC?

--

Phil

FireGod
06-04-2007, 11:33 PM
I guess a MAX323 would need to be provided for the PC interface.

FireGod
06-04-2007, 11:34 PM
Replace ALL the 595 chips

P. Short
06-04-2007, 11:37 PM
I see...but I'm not sure what the point is. Wouldn't it be easier to just buy a 64-channel dimmer board in the first place than to make 8 of those little boards? I don't see any cost savings...

--

Phil

FireGod
06-04-2007, 11:41 PM
My boards have the all the harware on the main board. This would be much cheaper.

P. Short
06-04-2007, 11:45 PM
I'm not sure what boards you are talking about, nor what hardware you mean. I was thinking about the coop board, but it might make sense if you had 595 boards with integrated SSRs, or something like that.

--

Phil

FireGod
06-04-2007, 11:50 PM
I designed and made my own boards last year with integated SSRs (128 channels) before any of the coops popped up.

Just a thought. It's a shame to throw away hardware that could be upgraded.

P. Short
06-04-2007, 11:56 PM
OK, only you know whether it is cheaper to create these postage stamp boards or to completely replace the big boards.

In your design I'm assuming that only one board has the oscillator populated? Also, the pinout on the oscillator is not right (power should be diagonally opposite the ground pin). Also, the polarity of the signals from the Renard chip are incorrect if you are using ULN2803 chips, although it is easy to correct this. These are just things that jumped out at me, I haven't done any thorough review of the board.

What type of headers are you thinking of using for the 595 sockets? Right-angle or straight?

--

Phil

FireGod
06-05-2007, 12:05 AM
Yes, I got the OSC + power con wrong, I'll fix it. I the output for the pins is good for me but it would just be a program revision for the other guys, right?

I threw it together in about 30 minuts so, yes, a reveiw would be nice.

Again, just dreaming. I lookd for a chip that would replace the 595 but the pinouts are all wrong for everything I looked at.

P. Short
06-05-2007, 12:16 AM
Now I'm going to have trouble sleeping tonight...I'll be trying to think up other ways of accomplishing this (saving the 128-channel 595 boards).

What I'm thinking now is to use one of this big PICs that you favor (28 pins is probably enough), followed by a CD4517 IC (128-bit s/r), some control logic. At each timeslot the PIC figures out which channels should be 'on', and broad-side loads that info into the s/r (as 16 byte-wide writes). The external hardware then shifts the data from 4517 s/r into the 595 chips...

This is, I think, doable. Using a PIC16F627 (clocked at 20 MHz) I did a similar thing for 64 channels (the 4517 wasn't needed because the 595 chips were in parallel, rather than series). Those PIC18F parts that you have used should be capable of doing this if they are clocked at 40 MHz, although it would require some pretty mean assembly language programming.

But, even if doable, probably way too much work for what it would be worth.

--

Phil

klanger
06-05-2007, 03:44 AM
While I don,t fully understand the science of it , i think i understand the concept, pull the 595 chips, plug in the new little board with the new chips etc and ta dah a dimming board, I like the idea, surely the cost of the little boards in a bulk coop would be cheaper than a whole new board.

Keep up the idea and i think a lot of people would go with it, a lot of us already have the coop 595 board and in the future would like to go dimming the cheapest way possible.

FireGod
06-05-2007, 09:31 AM
I wrote a program to output data from my field module to a 64 channel 595 system. With 64 channels of data the best it would do is updating the 595 bits every 1.4 ms. I guess that would at least provide 10 levels of dimming anyway.

I did not connect to a 595 IC, just measured it on the scope. I'll see if I can setup an actual test tonight with a 595 board and one SSR.

P. Short
06-05-2007, 10:05 AM
I can see that people don't want the discard the 595 boards that they have already purchased and spent a lot of time on. Some people, I think, will re-cycle the non-dimming boards for the non-critical parts of their displays, and add new boards for where they want dimming. Others will want to update their entire display to use dimming, without discarding the existing boards. The question for these people becomes 'what is the easiest, cheapest' way to do this.

The method that Firegod is proposing is certainly simple, and will work, and is not all that expensive. Meanwhile, I'm just thinking out loud about a different way of doing it. Rather than replacing the 595 chips, I'm wondering if there is a way to leave the 595 board (or the grinch board) the way that it is, and add a new little cheap inexpensive board up-front, in between the PC and the input-connector to the 595 board. The thought exercise isn't complete, but it looks to me like it could be done (for 64 channels) with one mid-range PIC (such as a PIC16F688 or a PIC16F627A), a CD4517, and maybe one or two SSI CMOS parts (plus the RS485 and zero-crossing circuits, of course). This would be less expensive than using 8 PIC16F688 parts, but takes a lot more design work.

For Firegod (with 128 channels) this would have to use a higher-end (higher clock rate) part, such as the PICs that he is already using for the 128-channel dimming system. And is would also probably require doing some assembly language work.

For me, this is mostly a thought exercise, since I don't have any 595 boards.

--

Phil

P. Short
06-05-2007, 10:07 AM
Firegod,

This is a little bit off-topic, but how is the 100-level dimming on the other project working out?

Are those 100 levels created by dividing the AC waveform into 100 equal-size time-slots, or are the time-slots of varying width?

--

Phil

A Marchini
06-05-2007, 12:27 PM
Now I'm going to have trouble sleeping tonight...I'll be trying to think up other ways of accomplishing this (saving the 128-channel 595 boards).

What I'm thinking now is to use one of this big PICs that you favor (28 pins is probably enough), followed by a CD4517 IC (128-bit s/r), some control logic. At each timeslot the PIC figures out which channels should be 'on', and broad-side loads that info into the s/r (as 16 byte-wide writes). The external hardware then shifts the data from 4517 s/r into the 595 chips...

This is, I think, doable. Using a PIC16F627 (clocked at 20 MHz) I did a similar thing for 64 channels (the 4517 wasn't needed because the 595 chips were in parallel, rather than series). Those PIC18F parts that you have used should be capable of doing this if they are clocked at 40 MHz, although it would require some pretty mean assembly language programming.

But, even if doable, probably way too much work for what it would be worth.

--

Phil

I was thinking that a solution involving a 597 could be used, along with an external counter , and a high speed external clock.
The pic would just write out the 8 bit values, but the external hardware would deal with the clocking into the 595s. I think that might free up cycles for doing the rest of the dimming stuf.
The counter would generate the latch automagically, some jumper or something would set the number of 595 on the output, or the PIC could do it.

I was considering this as an addition to off the shelf USB-parallel port converters , so that vixen would just have to print data to the port and it would fire off the bits automatically to the 595 boards.

Synchronization would be an issue that I haven't come up with a good answer for, unfortunately.

Tony

FireGod
06-05-2007, 01:11 PM
Firegod,

This is a little bit off-topic, but how is the 100-level dimming on the other project working out?

Are those 100 levels created by dividing the AC waveform into 100 equal-size time-slots, or are the time-slots of varying width?

--

Phil

I am using the interupt of a timer to increment a 0.167 ms counter that counts to 100 and the count is the dimming level.

On your earlier comment, the test I did this morning WAS to put a small 40MHz PIC up front but I guess my program is a bit clunky and about 10 times too slow. It would offer 10 dimming leveles to 64 channels of a 595.

P. Short
06-05-2007, 01:32 PM
Thanks.

By 10 times too slow do you mean that it won't work at all, or does it mean that it will work if you do more work on the code?

I've been going back over the design of my 64-channel Renard. If I back off to 100 dimmer levels (instead of 256), I think that my Renard64 design could be made to dim a 595 with one external chip (a CD4517) and some relatively minor code changes. This design is not PWM, though, and it would be very hard (maybe impossible) to convert to PWM. At this time, though, I have some qualms about going down to only 100 dimmer levels. This is effectively only 50 levels to my thinking, since almost all of the action happens at the middle 50% of the range (or so).

--

Phil

FireGod
06-05-2007, 01:36 PM
My DS pulse to the 595 occured in 1.4ms intervals. to have 100 dimming levels you need to update in 0.167ms intervals.

P. Short
06-05-2007, 01:38 PM
Doesn't it actually have to be twice that fast, since you have to generate the pulses every half-cycle (i.e. every 8.33 ms)?

--

Phil

FireGod
06-05-2007, 01:45 PM
I was still thinking in PWM terms, you are correct. My data transfer is 20 times too slow.

FireGod
06-05-2007, 09:52 PM
Well I tried to change my code to have less instructions and I was able to eliminate quite a few but it did not help at all. I still had a DS pulse of ~1.4ms. I was trying to do a PWM scheme over an entire cycle so I could had 16.7ms to work with.

I went ahead an connected it to a 595 and SSR and it did dim but it was not smooth, had a lot of flashing and I found it to be completly unacceptable. So....I am no longer chasing the up front IC to feed the 595 data because evidently I don't have the know how to get it done and I have about 6 other projects that I need to be working on, this one is not even on the list, I was just dreaming.

P. Short
06-06-2007, 10:13 AM
Tony,

At first I didn't understand what you were proposing (my head was in other places at the time), but it finally came to me. I think that would work fairly well, perhaps better than my idea. The difference is that I was thinking of having the PIC load up an entire 64 bit s/r in parallel (the 4517), and then having logic shift the data out to the 595 chips. Your solution is similar, except only 8 bits are parallel-loaded before the shifting begins. Right now either way seems to take about 3 or 4 chips outside of the PIC.

Onother idea might be to use the synchronous mode of the PIC uart to send data out to the 595 chips (although this might mean that communications with the host might have to be done with a software uart).
--

Phil

A Marchini
06-06-2007, 12:55 PM
Tony,

Your solution is similar, except only 8 bits are parallel-loaded before the shifting begins. Right now either way seems to take about 3 or 4 chips outside of the PIC.

Onother idea might be to use the synchronous mode of the PIC uart to send data out to the 595 chips (although this might mean that communications with the host might have to be done with a software uart).
--

Phil

Yeah, that would be the way, also it would be externally clocked at high speed (probably from the pic clock) so you could do a write and latch in 3 instructions, and by the time you made it to the next latch it would be already shifted into the 595s. ... I don't know if tightening the loop up that much helps all that much. I haven't looked at the numbers.

I had looked at the data sheet of one of the synchronous modes of the PICs but never took it anywhere. I just suggested a way back that it might be able to handle the show.
PICs are cheap, use 2 for each 64 channels , divide up the work and simplify the software design. Especially if you are dividing it up over a 64 channel board or even two.

There are so many fun ideas, never seems to be any time.
Tony

A Marchini
06-06-2007, 01:09 PM
Tony,

shifting begins. Right now either way seems to take about 3 or 4 chips outside of the PIC.

--

Phil

I was thinking about this , and you are right.
HC597 - shift register
2 74HC00 for clock generation and synchronization
1 74?? 4 bit resettable clock for counting out 8 clocks precisily.

I am still thinking of an interface to glue onto those USB -Parallel port devices. Printing to the 595s so to speak.

Tony

P. Short
06-07-2007, 10:40 AM
One variation that might work would be to just an HC165 outside of the PIC, and clock it in software. This is simpler that generating a proper clock in hardware, but faster than doing all of the serialization in firmware. This should be fast enough for handling 100 levels of dimming.

Another possibility is to use a PIC18F1220 or PIC18F1230. These have the same pinout ast the PIC12F627 that was looking at, but they can be clocked to 40 MHz. This is all that you would need for a 64-channel/100-level converter (nothing external other than crystal, caps, and RS485 i/f).

--

Phil

P. Short
06-08-2007, 10:54 AM
For 64-channels, 100 dimmer levels I've come up with a fairly simple scheme for dimming the Olsen 595 with only a PIC16F688 (although PWM operation requires an additional HC00 chip). Pretty cheap, although the drawback is that the 595 chips are clocked at 1.25 MHz, which is faster than I'm comfortable with over any distance more than a foot or two.

The internal software would be almost the same as the current Renard, except that the following code needs to be executed 64 times for each timer interrupt:



movwf PORTA
decfsz ctr_channel0,f
bsf PORTA,SER_BIT
bsf PORTA,CLK_BIT


This sequence is equivalent to 256 instructions, and takes about 51.2 uS to execute (out of 80 uS or so per time slot for 100 dimmer level operation. WIth a PIC18F1220 (clocked at 40 MHz), this method could handle 128 channels, but the clock going out to the 595 chips also doubles to 2.5 MHz.

--

Phil

A Marchini
06-08-2007, 12:59 PM
For 64-channels, 100 dimmer levels I've come up with a fairly simple scheme for dimming the Olsen 595 with only a PIC16F688 (although PWM operation requires an additional HC00 chip). Pretty cheap, although the drawback is that the 595 chips are clocked at 1.25 MHz, which is faster than I'm comfortable with over any distance more than a foot or two.

Phil

I think that it is reasonable to stipulate that the dimmer circuit be virtually in contact with the 595s in question, for just that reason. Maybe add a little to the board power input capacitance in response to the increasing switching (I know , it probably negligible but a little more couldn't hurt).

These devices are going to make prior investment in 595 boards more valuable, and sort of like a stepping stone.

Tony

P. Short
06-08-2007, 01:07 PM
It could actually be a small piggy-back board like Firegod was first proposing. However, it would have on it one (the first) 595 chip in addition to the oscillator and the PIC. If PWM is needed (as it would be for proper LED operation), then there also needs to be a HC00 and the last 595 chip on the piggy-back board. It should not be too hard to make it straddle the first and last 595 chips on the coop-595 board.

For his board Firegod would need to have two of these boards, and would need to cut the clock and latch-enable lines between his eighth and ninth chips (speculative on my part, since I haven't seen the routing on his 128-channel board). His first approach is still viable, although a bit more expensive.

--

Phil

wjohn
06-08-2007, 07:06 PM
when you have a circuit, i'll do the PCB design.

P. Short
06-11-2007, 01:41 PM
Here is a schematic fragment for the discussion. It shows RJ45 connections to the 595 coop board, because I don't consider the form factor to be decided yet.

The HC00 chip is used to implement PWM functionality outside if the PIC, because there isn't enough instruction bandwidth to do it in firmware (without going up to a 40 MHz part in an 18-pin package).

--

Phil

teberle
06-18-2007, 11:23 AM
So has this died?

P. Short
06-18-2007, 01:36 PM
Just in hibernation.

At this point I have the design partially completed for two versions. A schematic fragment for the simpler one is shown above, which is good for about 100 dimmer levels. Most of my time lately has been spent on the design of a more complicated version that is capable of handling 256 dimmer levels, requiring a number of chips outside of the PIC. This is my favorite one, because it is harder for me to design, and because DynamoBen has led me to doubt that 100 levels is the right thing.

Just now (after writing the above) I ran a little test comparing 100 dimmer levels versus 256 levels (using some of my own test s/w on a FreeBSD system) over a 10 second interval. Using 100 levels with some nightlight bulbs, there are some 'stepping' effects that are just barely discernable in a fairly brightly lit environment. I'll do some more testing tonight using some mini-lights, and see what it looks like then. My eyes are quite untrained, though, and I suspect that there are other people who would find these effects to be much more noticeable than I do.

This 'project' may appear to go into hibernation from time to time, since I don't have any 595 boards myself, and am working on it just for the fun of it.

--

Phil

ErnieHorning
06-18-2007, 02:24 PM
Do you think that this will end up being practical? I understand the design challenge though, even if its not.

The motivation for the pure discrete one that I did was because there were so many posts that said they wanted it, tried and failed or said that it just couldn’t be done. The impossible is the most fun to work on. :D

P. Short
06-18-2007, 03:15 PM
Don't know. As you can see, the 100-level version is pretty simple, involving just three ICs (plus maybe a regulator). The current 256-level design takes six ICs beyond the PIC and 485 chip. I'm not sure that going to even the fastest practical PIC (40 MHz) would solve the 256-level problem without external ICs.

--

Phil

P. Short
06-19-2007, 10:54 AM
Update:

Last night I did a little bit more testing to see if there were any discernable stair-stepping effects with 100 levels of dimming, using both individual C7 bulbs and a 100-light mini-string. It did appear to me that I could see some stepping artifacts with 100 levels (although not with 256 levels). They were barely discernable, so I think that most people would not notice them. They would be evident, though, to someone with a sensitive or trained eye.

--

Phil

Macrosill
06-19-2007, 12:06 PM
The stepping artifact might be a concern if someone was dimming a single bulb and the spectators attention was keyed in on that one unit. In our displays there are thousands of lights and upwards of hundreds of channels constantly changing. I think something slight might not even be noticed by a trained eye unless they key in on one thing. There is usually so much going on that most do not even notice if entire strings of lights are not working. The eye is overwhelmed with all the activity and grand scheme of things.

Last year I had 3 sets of lights out on my Mega Tree by the seasons end. No one and I mean No one I spoke to could even see it, even if I told them about it. I saw it only because I know where ever string is located, where it runs to, where it connects and so on.

So to summarize, I would not be too worried about a slight dimming step or artifact. No one will notice it. Even if they do they will think it is supposed to happen and believe it is part of the show.

I would opt for the simpler "conversion". It may just be a price you have to pay if you want to convert your 595 to dimming.

BillAd
06-19-2007, 12:16 PM
Phil,

This will be a great enhancement for our existing 595 boards. In my display there is so much going on I doubt the stepping effect will be noticed by anyone so I have no concerns. The stability and distance gained from using a RS484 communication stream is what I was looking for so dimming is a hugh bonus! Thank-you!

Bill

ErnieHorning
06-19-2007, 04:37 PM
Those multifunction mini strings have the same stepping look at the lower end and no one seems to notice it. Even when I call attention to it, no one seems to care. I guess it’s just the Engineer in me.

I don’t think anyone is really going to care. The fact that their ‘595 can now do dimming is a big plus. Besides if you throw too much hardware at it, the cost will be close enough that it’s probably better to chuck the ‘595 and build a Renard.

Oh, congrats Phil on being the one to get this to work!

P. Short
06-19-2007, 05:05 PM
That brings up another question...what is a reasonable cost for this thing? At some point it makes more sense just to chuck the 595 board (or use it in non-critical areas) and get a whole new controller for dimming.

--

Phil

P. Short
06-19-2007, 06:17 PM
There is a way to get 192 levels (or so), with hardware similar to the drawing on the previous page. It requires the use of a PIC with both a UART and the CCP module, such as the PIC16F627A. The loop for outputting data to the 595 looks like this:



movlw 1
addwf ctr_ckt0,f
rrf PORTA,f
addwf ctr_ckt1,f
rrf PORTA,f
etc


and uses the PWM output from the CCP module to create the clock to the 595 chips. The firmware must make sure that there are exactly 64 clocks going to the 595, which will be a bit delicate to implement. Having 192 dimmer levels should be good enough to eliminate most of the residual stepping effects.

--

Phil

P. Short
06-20-2007, 02:07 PM
Here is a schematic fragment for the renard-595 converter with 192 levels. After a little bit of testing it looks like it can work. The biggest technical concern that I have now is the issue of RFI emissions, as it uses a 2.5 MHz clock to send data to the 595 chips.

There is still more debugging work needed, though.

--

Phil

P. Short
06-20-2007, 03:17 PM
A slightly simpler schematic fragment...

P. Short
06-20-2007, 04:34 PM
Here is an untested version of the code (for reference only). I was using it to look at the timing of the signals on pins 17 and 9 of the PIC, to see how easy it is to control the PWM output from the PIC.

--

Phil

teberle
06-20-2007, 05:07 PM
So how many dimmable channels will be available on the 595?

P. Short
06-20-2007, 05:13 PM
You mean total per serial port? Just like Renard, it depends on the update rate and the baud rate. At 57600 baud, 100 ms, worst case channel count would be 288. If the protocol is changed (or Vixen avoids the dimmer levels that slow things down), the number is doubled.

--

Phil

teberle
06-20-2007, 09:28 PM
Since the 595 has 64 controllable ports how many of them will be dimmable?

ErnieHorning
06-20-2007, 09:40 PM
All of them! All the first, second and third boards.

MarkL
06-20-2007, 10:25 PM
In the schematics you're showing the "to 595-coop" and "from 595-coop." If one wanted to control multiple 595 boards would you chain the 595's together and feed the last one back to this converter board or is one converter board required per 595 board?

I'm very interested in this project and appreciate all your efforts Phil. After playing with some sequencing, I'm seeing how much smoother some effects are with dimming capability. So, I would love to convert my two 595's to dimming. I have to think one of these converters is much cheaper than building a 64 channel Renard from scratch.

Mark

P. Short
06-20-2007, 10:33 PM
One 64-channel coop board per converter.

--

Phil

MarkL
06-21-2007, 11:40 AM
So is there a way to chain the converter boards together (obviously with changes to the schematic and probably some firmware changes) or would an additional serial port be required for each 64 channel converter+595 combo?

Sorry for sounding dense, but Ernie's and your earlier comments seem to indicate the ability to run >64 channels on one serial port.

That brings up another question. Can the converter be on the end of a chain of other Renard boards? For example, could I do the following?

PC --> Renard64 --> 595Converter --> 595

Thanks.
Mark

P. Short
06-21-2007, 12:45 PM
As currently proposed, there can only be one 595 board per converter board, but the converter boards can be chained together. And, so long as the protocol remains what it is now, the converter boards can be freely intermixed with Renard boards. This capability is already built into the schematic fragment and the firmware draft.

So, one possible setup may look like this:


PC
|
V
Renard8
|
V
Converter -> 595
|
V
Converter -> 595
|
V
Renard

--

Phil

Macrosill
06-21-2007, 01:03 PM
Mark,
The above possibility posted by Phil is utilizing the serial port of a pc or a usb serial converter. A 595 upto to 1024 channels can still be controlled off a parallel port of the same pc. So you can use any combination of Renards and 595 converters off the serial port and any number of 595s off a parallel port simultaneously.

ErnieHorning
06-21-2007, 01:24 PM
So you can use any combination of Renards and 595 converters off the serial port...
Up to 288 total channels, then you need to add another serial port.

P. Short
06-21-2007, 02:03 PM
I've started a wiki page on this topic...feel free to edit it or the accompanying discussion page.

--

Phil

Matt
06-21-2007, 05:39 PM
I'm designing a concept PCB, and I have a quick question: what type of package is Y1? (a part number would be helpful).

Thanks,
-Matt

P. Short
06-21-2007, 06:22 PM
Wjohn is also designing a board.

The crystal that I've used in the past for that part is mouser AB-20.000MHZ-B2 (the parts that I have on-hand). Also, bear in mind that the firmware is untested (and therefore to be considered non-functional), so keep in mind that this is truly a concept board until I can get more testing done.

--

Phil

klanger
06-21-2007, 09:09 PM
Hi Phil,
Reading the posts and the Wiki it seems the converter needs to be used after a Renard board. Is this so or can it be used with just a 595?
i.e PC to converter to 595

Thanks
Kevin

P. Short
06-21-2007, 09:16 PM
No, it can be used by itself. I already changed the wiki text to try and clarify this, but maybe I need to add another diagram.

--

Phil

P. Short
06-22-2007, 06:50 PM
Here is a semi-functional version of the firmware. This version appears to be successfully receiving renard-style frames, and the outputs of the first (and only) 595 chip appear to be doing the right thing in response to these frames. So this version should be considered partially tested (at best), but can be use to experiment with.

There may be more functionality added in the near future (such as status LEDs), and the pinout is subject to change as the PCB is laid out.

--

Phil

P. Short
06-24-2007, 09:33 PM
The 20070622 version of the firmware is going to have problems with daisy-chaining to another controller, I'm working on a fix.

--

Phi

MarkL
06-24-2007, 10:57 PM
I thought I read somewhere that the PIC used is only programmable via ICSP. Is this true?

In any case, this device is too big for my pickit1. Are there cheap ICSP programmers available (or is it cheap and relatively easy to build one)?

Mark

P. Short
06-25-2007, 12:14 AM
There is a way to use your PicKit1 with that part.

First, you need to create a socket adaptor of some sort to connect the PIC16F627 to your programmer.

Second, that PIC cannot be programmed from the IDE. Instead, you will need to use the "PicKit 1 Classic" stand-along programming software.

A bit convoluted, but it can be done. I've used both the PG164101 (programmer from PicKit1) and the PG164120 (programmer from PicKit2) for this purpose. Both of these programmers come with just a 6-pin in-line connector, rather than a socket, and I always include the mating connector on the PCBs that I've designed. YMMV.

--

Phil

wjohn
07-02-2007, 02:07 AM
The PCB design is just about ready, I'll start another thread for a Beta COOP for the REN-C.

http://www.doityourselfchristmas.com/forum/viewtopic.php?p=1597#1597

It is listed under the COOP Section.

BillAd
07-02-2007, 08:52 AM
wjohn,

So many Coop's underway. As a second option could you post the PCB design and parts list for those that prefer to etch their own boards? Perhaps an addition to the Wiki? Thanks.

Bill

P. Short
07-02-2007, 11:47 AM
That design is not a particularly good candidate for a self-etch board, IMO. There are a lot of traces on both sides of the board, and they are all fairly thin. If you want to do it yourself outside of the coop, the stripboard approach might be better.

--

Phil

BillAd
07-02-2007, 02:12 PM
Phil,

Thanks for the comments. I'm not so worried about keeping the board tiny so to rework the layout to allow for a single sided etched board with a few wire jumpers will be ok. The circuit diagram on the wiki looks fairly simple and a part's list will help me layout component spacing. A picture of the current pcb design will help confirm the diagram is consistent. Perhaps I’m missing the big picture so feel free to comment as such, thanks.

Also I would like to interface this circuit to a 48 channel 595 boards. Can I define this smaller board to Vixen as having 64 channels and use the standard firmware (of course ignoring the missing 24 channels)?

Finally I’m wondering how the feed from pin 8 of the RJ45 jack “From 595 Out” is used?

Your thoughts and advice is appreciated.

Bill

P. Short
07-02-2007, 03:19 PM
The feedback from the RJ45 "From 595 Out" is used to generate a PWM waveform to the SSRs. The PIC16F627 isn't fast enough to generate the PWM waveform without using external feedback (at least, I haven't been able to figure out how to do it). The waveform to the SSRs will be a 40 uS (or so) pulse (instead of the PWM waveform) if you leave this connector open.

The board is designed for use with exactly 64 channels. If you want PWM operation, you need a 64-channel 595 controller (unless you want to change the firmware yourself). If you don't need PWM operation and leave out the feedback connector mentioned above, you could do what you proposed above (program vixen for 64 channels, but just use the first 48).

As for the BOM, I'm sure that will be added to the wiki pretty soon so that the people doing the Beta testing can buy parts.

--

Phil

lytnin
08-10-2007, 03:53 AM
Received my REN-C Board, and have started sourcing parts. :D

A quick question about the LED's on it.
Can I just swap the specified green LED's, for the red ones I've got for my LedTriks board (since I have a spare 200+) or do I need to change anything :?: - SIP etc.

Cheers

P. Short
08-10-2007, 11:30 AM
That should be OK, there hasn't been any tuning of the resistor values or LED colors.

--

Phil

wjohn
08-10-2007, 07:07 PM
Received my REN-C Board, and have started sourcing parts. :D

A quick question about the LED's on it.
Can I just swap the specified green LED's, for the red ones I've got for my LedTriks board (since I have a spare 200+) or do I need to change anything :?: - SIP etc.

Cheers

Dont you like Green? they match the PCB nicely.

any 3mm LED will do, 5mm LED are just too big, unless you were to file down the side slightly to fit the PCB spacing.


I went for the smallest practical PCB we could design.

BuzzKill
08-15-2007, 10:52 AM
Okay...
I see the Ren-C board. (very cool, btw) What's up with the ZC "generator"? I don't see that mentioned in this thread or on the wiki. What is the secret sauce in that box? Or is ZC available on the board itself?

Any chance of getting one of these before halloween?

wjohn
08-15-2007, 12:56 PM
Buzz,

You get need a ZC signal to provide ZC reference. An easy way to generate ZC is from a CT transformer and a couple of diodes.

P. Short
08-15-2007, 01:13 PM
If you really want to use it, the H11AA1 circuit from Ernie's How-To should work fine (bring the outputs of the H11AA1 opto-isolator in through JP3-1 and JP3-2). My preference is for the transformer circuit, as the high-voltage signals are kept further away from the low-voltage circuits.

--

Phil

BuzzKill
10-02-2007, 10:22 AM
What's the dealio? Where did everybody go? Is this thing dead? Everybody was like all gung-ho and then P00F! Nothing. I would LOVE to get one of these going by halloween. I can do it if I can get a board. Anybody got a board? What is the hold up? Am I asking to many questions? Are we there yet? How 'bout now? :lol:

Jeff Millard
10-02-2007, 04:00 PM
I don't know about the rest, but I have completed the Ren-C and the Ren-T for Zero cross. I haven't programmed the PIC, or even assembled the cables to connect it all together. It's just getting too close to show time and I use LOR for my display. I feel like I let Phil and John down for not getting further along, but I bet my reason for postponing testing isn't uncommon.

Jeff

Dan Ross
10-02-2007, 04:18 PM
I have a few REN-C's headed my way. Once I get them put together and working I'll post an update.

If you want some send an PM to wjohn he might have some left.

Dan Ross
10-05-2007, 09:52 PM
I've had success. I have one of my REN-C's built and working. Here's a short clip of it in action.

<embed src="http://www.youtube.com/v/_vaDzgyTQXY" type="application/x-shockwave-flash" width="425" height="350"> </embed>

Wayne J
10-05-2007, 10:25 PM
Awesome!

Congrats!

BuzzKill
10-06-2007, 02:49 PM
Are you having the issue where it flickers at the lower dim levels?

I have the parts and pic programmer ready to go. Just waiting on boards to arrive. I have the 595 and 8 SSR's ready to go as well.

I'm going to run Halloween on 32 channels. Can't wait for huge throbbing red flood lights the front of the house to a beating heart sound track.

Dan Ross
10-06-2007, 05:12 PM
I haven't noticed any filckering yet. I will play with it more next week.