Mctrivia,· have you read the whole thread?·· Here's a recap of·the boards we are building.·
1 Prop development board connected to the master driver board.
8-10 slave boards (40-64 relays each)
70+ distribution boards to connect to the slave boards via cat 5 cable.
we are on a real limited budget for the electronics and development costs so paying a company for that many boards is out of the question unless it's like $1 each board.· Every place i've looked into has been at least $100 for one slave board to be printed and drilled.· I'd love to get all of them professionally made, but we are just a private/non profit group and don't have a lot to spend each year.
I'll still take help from anyone on designing the boards so I can print and etch·them myself. I am just about done with my cnc for all of the drilling so that will help and I have a bunch of friends willing to help solder the points and hardware.
We're also down to about a month before we can start building the pyro's themselves. We live in North Dakota and have had one hell of winter and can't build anything till I can kill the furnace in the shop for the summer and it needs to be warm enough outside to let powder dry and grind in the ball mills.
yes I am 26. I have read the entire thread but I forgot the distance between your boards and controller was so far.
making boards your self is great though making double sided boards can be difficult.
4pcb.com offers $600 off first order which depending on order size can be free.
if you are doing any of the layout in eagle I would be happy to help.
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chaosgk, sorry for not posting this sooner, got tied up on a call and it slipped my mind. The line drivers and receivers should each have a 0.1uF capacitor between VCC and GND. By the way, are you planning on putting all 7 TPICS and 56 relays on one board?
Yes, I think I am going with 7 tpics per slave right now, I don't know if they will be on one board or if a slave will consist of a couple of boards stacked. I'm having trouble fitting that much stuff on a 10"x12" board. The CNC is just about done, it moves in X/Y/Z Axis's, just need to get the table attached and mount all of the wiring and work out some heat issues with my controller cards. Once that is done (tonight), I'll get to work on building the prototype of a slave board and get some testing done on those. I have about 200 .1uf capacitors on the way and 1500 1.2k 1/4w resitors for the LED's. I punched the numbers for voltage in, current and desired voltage and came up with 1.2k for my LED's hope this works out or i'm out $7 [noparse]:)[/noparse]
I have 15 drivers and receivers on the way from hong kong, they matched the ones we had spec'd earlier. I think I will be using dip sockets for most of the chips that will be on the boards, (ie drivers, receivers, and tpics). I still need to order the tpics and anothe color or LEDs for the relay status lights. Green=good ignitor, Red=active relay.
300ohm is min required for 3v 30ma led with 12v supply. what is the voltage and current ratings?
larger means dimmer but still works
voltage in-voltage diode
current desired
gives minimum resister value
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Need to make your prop design easier or secure? Get a PropMod has crystal, eeprom, and programing header in a 40 pin dip 0.7" pitch module with uSD reader, and RTC options.
Oh forgot power min is
(voltage in-voltage diode)*current desired
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Need to make your prop design easier or secure? Get a PropMod has crystal, eeprom, and programing header in a 40 pin dip 0.7" pitch module with uSD reader, and RTC options.
if I remember correctly your using 24v 700 would be needed at 1W
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Need to make your prop design easier or secure? Get a PropMod has crystal, eeprom, and programing header in a 40 pin dip 0.7" pitch module with uSD reader, and RTC options.
You are correct, the input voltage is 24v, the working voltage is 3.7v (I've tested at this and they work fine).· And I don't have the mAh specs, but they are low, my multimeter puts out enough current on contenuity testing to light them up a little.· I would guess in the 10-20mah rating.· These are tiny led's, about 2-3mm across the entire chip. These are surface mount chip type LED's.· If the resistors don't work, I'm out $7, oohh, wouldn't be the first time I wasted money on a something for a project and not used it. ·
ok then you are running the registers at 102% of there rating they should be fine.
you are providing 12mA to the led probably under max current but not necessary
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Need to make your prop design easier or secure? Get a PropMod has crystal, eeprom, and programing header in a 40 pin dip 0.7" pitch module with uSD reader, and RTC options.
chaosgk, 1.2k will give you a bit less than 20mA which is more than enough current. A 10x12 board with the line receiver, 7 TPICS, 56 relays, capacitors, connectors, etc will probably be a bit crowded.
Yeah, from my initial designs on the boards, I am having touble fitting everything on there with all of the traces and routing that needs to go to all of the places, along with having larger traces for the 24v power as well.· I may end up using some type of daughter board on the slaves to get the full 56 relays per slave I want, plus that would allow me to put up to 10 tpics on a slave if I split it to two boards per slave.· I was thinking of using some type of ribbon cable between the two boards on the slave for the signals.· Any problems with signal strength with that?· A single IDE or Floppy ribbon should be able to handle the low voltage for the chips and data and have a 20ga pair for the 24v feed.· It would be a very short jump between boards, like 2" or less.
The CNC is operational now, I have some cleanup to do on it and build a stand for it this week, but it cuts and is very accurate.· I have some tweaking to do with the X axis over long runs and really need to learn the software end of it.
I should be able to start drawing up the boards again.
20 gauge a little thin for the switch current but if that is not running though ribbon it shouldlf be fine.
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Need to make your prop design easier or secure? Get a PropMod has crystal, eeprom, and programing header in a 40 pin dip 0.7" pitch module with uSD reader, and RTC options.
My original thought was to have 1 TPIC and 8 relays per board with 7 boards connected by ribbon cables, so joining 2 boards with ribbon cables for the logic voltage and signals should not be a problem. I would make the 24V connection separate and a bit beefier to avoid potential problems from high current spikes when the igniters are fired. How about 2 6"x10" boards? Unless the relays are fairly large you should be able to run the TPICS down the center with relays on each side like the second layout I suggested a while back.
Adding more TPICS to a board would complicate the software. I had planned on having commands that were one or two longs.
The time command would be 1 long consisting of an 8 bit command and a 24 bit time (in mSec from T0).
The fire command would be 2 longs consisting of an 8 bit command/slave number and 24 + 32 bits where a 1 bit would fire the corresponding relay/igniter.
Adding 3 more TPICS would mean adding a third long and using 24 of the 32 bits to control them. Much easier to stick to 7 TPICS, 56 relays per slave and add another slave if more than 448 relays are required. I planned on having a 4 bit slave address, allowing up to 16 slaves which would be 896 relays. Do you think you will need more than that? If so I can go to a 5 or 6 bit address allowing 32 or 64 slaves.
No, 896 relays should be fine, if we go above that, we will need to redesign things anyway, I can't see ever going beyond that point.
As far as the 20awg, I can bump that up to 18 or 16 easy enough. So do we want to go with 7 or 8 tpics per slave? I am thinking it will be 8 tpics per slave with 7 of the channels being used (7 wires per RJ45 for +24v and 1 wire for common).
I would suggest 7 tpics per slave. It makes the software to output commands much cleaner. Having to account for every eighth bit not being used makes things more difficult. Laying the board out is a one time thing, creating a program timing sequence will be done more frequently so I want to make that as simple and intuitive as possible. Besides, why put an extra TPIC on the board if you don' need to.
Ok, I'll just have to figure out how to split all of the relay channels because one relay from each tpic will need to carry over to something like a spare RJ45 line or find a use for that 8th output of the tpics somewhere as I can only push 7 channels across a cat5 line.
I wouldn't worry about how to split them up. Connect 8 relays to each TPIC, and 7 relays to each RJ45. As far as the software is concerned we will be sending out 56 bits of data to each slave. The fact that there are 7 TPICS receiving 8 bits each makes no difference to the software. That the relays are connected to the RJ45 connectors in groups of 7 also makes no difference. As far as the software is concerned each slave has a 56 bit register connected to 56 relays.
TPIC 1 will receive bits 1 to 8, and will be connected to relays 1 to 8.
TPIC 2 will receive bits 9 to 16 and will be connected to relays 9 to 16, etc., etc. so TPIC 7 will receive bits 49 to 56.
RJ45-1 will be connected to relays 1 to 7
RJ45-2 will be connected to relays 8 to 14, etc., etc., so RJ45-8 will be connected to relays 50 to 56.
No problems. If I want to set off the device connected to relay 37 on slave 1 I clear all 56 bits, set bit 37 to 1, shift out the 56 data bits, and transfer the data to the output at the appropriate time.
I was looking at it more from a board design issue. I was going to have each tpic and it's relays grouped together to run out to the RJ45 that goes with it. With 8 relays for each tpic, I have one left over from each that will need to be assigned to the next RJ45 connector in the line. I was thinking of simplicity reasons to maybe have the 8th relay carry over on each tpic to a different RJ45 and have all of the 8th lines go to that one? I have to draw it out.
Are you thinking the other way, just continue with moving the 8th one down each time.
First one will carry over 1, 2nd will carry over 2, 3rd will carry over 3 and so on until the end where the 8th will hold everything from the 7th tpic except #1?
I was thinking more in terms of the relays being evenly spaced (as close together as practical) with the tpics on one side and the pins or solder pads from the contacts on the other side. Usually the relay coil connections are on one end of the relay base and the contacts on the other end. It would just be a matter of centering the tpics on eight relays, and the contacts on 7 relays. The other option is to put one pad in front of each relay and a ground every 7 relays or 8 grounds grouped together. Were you by any chance planning to solder the RJ45 directly to the board?
Yes, the RJ45's are getting soldered directly to the board. For those I have 12 port RJ45 panels that are board mount. We have been flooding here so my nights since easter have consisted of putting up sandbags to direct water away from my house and driveway so all projects were put on hold for a little bit.
Sorry to hear about the flooding. Hope you manage to stay dry.
On the master do you want 12 ports out or do you want to put 2 panels on for 16 or 24 ports. Keep in mind that each port will require a driver, and going beyond 16 drivers will require another address line. Best to lay the board out for as many drivers as you may want, although you only need to mount as many as you need on the board.
How do you want to connect them on the slaves? I am assuming one port for input so will it be either 8 for output, or distribute them more evenly (10x5 connections + 1x6 connections)?
Yeah, the house and garage stayed dry. The yard flooded a little bit so there is a lot of cleanup to do when things dry out, but we are past the high point and it is going down so all is good.
Anyway, I have 15 drivers and receivers on the way so I think I will plan for that many on the board. 12 will get mounted in the panel of 12 ports and the other 3 will be aux with the drivers installed but the ports not put in place yet. I will probably just put a 8 pin header in for the other 3 ports.
I am not sure what you are getting at on the slaves for the 10x5 + 1x6 for connections.
I would expect to use one of the 12 ports for input and another 8 for output and have a couple that aren't used.
I'm not sure how it will work if I have to stack boards in the slaves. I may see if I can have a smaller board of tpics that all wire into a couple of 40 pin headers and connect those headers via ribbon to a relay board...... hmm. I'll have to look into that.
What I meant by 10x5 + 1x6 was that you have 12 ports, one port for input and 11 for output so if you wanted to use all the output ports you could have 5 outputs on 10 of the ports and 6 outputs on one port. I agree with you that it makes more sense to use one for input, eight for output, and leave three unused or used for something else.
I also agree that it may be better to have the relays on one board and the tpics on another. How big is the relay footprint?
For the Master:
The protoboard has 32 I/O pins. Four are used for programming and the eeprom, leaving 28 available. Five are used to send control signals to the slave leaving 23 available for selecting slaves and other uses. These five lines will need five resistors to go from 3.3V prop pins to 5.0V of the drivers.
For selecting slaves we have 2 choices. We can use one I/O line per slave which requires 15 lines with 15 resistors to go from 3.3V of the prop to 5.0V of the drivers. The other option is to use one or two logic chips to do the driver selection and would require 5 lines and 5 resistors (or possibly fewer) between the prop and the logic chips.
We had trouble with the matrix idea because of not being able to address every relay independently and in my opinion it is much easier with Kwinn's current addressing scheme to program multiple relays to fire at the same time if need be.· Thanks for the input though, I did give A LOT of consideration to the matrix idea when I started drawing it up and couldn't find an easy solution on the programming side of it and the PCB layout seemed to be a hastle as well.· I did give it a lot of thought though, thanks.
To anwer your question on the relays, I believe they are 5mm x 10mm.· pretty small.· It's not the question of fitting all of the relays on the board, it's the trace space I need for the relays. I know I can go pretty small on the traces that activate the relays, but the ones that drive the ignitor need to be pretty good size so fitting that many traces in a compact space is posing a slight space issue.
The other problem with running less then 7 outputs on each jack is cat5 cable.· We have more than enough cable but the less igniters we have on a cable, the more cable we need to use.·
The pyro racks will be based on multiples of 7 so we can run only 3 cables to a 21 shot rack vs 5 cables for the same rack if you catch my drift.
It's all comes down to efficiency on shooting day.· We hope to have everything completed at least a week before the 4th so on the 4th we can get up early in the morning, put all the racks in their places, plug cat 5 cables into all the jacks check for contenuity and relax for the rest of the day until dark.
I would actually like to be able to enjoy some time hanging with family and friends for once.
Again, thank you to everyone that is helping with this, I know I couldn't do any of this alone. ·
I agree that 7 outputs per jack is preferable, but you are the one who has done this before so I thought I would bring the other options to your attention. The problem is going to be the traces going to the RJ45 12 port panel. Can you get a heavy enough trace to them? I am particularly concerned with the common connection. It will carry the sum current of igniters that are triggered simultaneously. Have you considered putting the relays on the distribution boards? I know that means running 24V to the distribution boards but it also simplifies the slave layout.
I did look at it before and I think the current design will be fine. I already have the 500 relays for the system.· As far as the power supplies, I may yet run separate power to each one, but the current draw of the ignitors is small. I am yet to do a current test on them, but I believe with a short cable length, even a 9 volt battery will trigger one.· The igniters have a single strand of 40-50AWG nichrome wire and it takes hardly anything to get them to burn so there will not be a very large draw on the system with multiples lighting at the same time.
I completely get where you are coming from with the matrix idea, but I think in the long run, the 8 relays per tpic are the way to go.· I will be ordering 100 tpics so they are coming in at bulk price of $1.55 each I think, pretty good price off the regular $2.50 each.
I should have some time on sunday to start drawing up the PCB again and we'll see where that goes. I will do a small test one of maybe 8 or 16 relays with the receivers installed and see where we are at after that.
I had some trouble with my X axis of my new CNC that mostly have fixed.· I went from using 5/16th drive rod to 1/2".· What a difference.· I was limited to 18" travel/min with the 5/16th.· Testing last night with the 1/2", I was up to 75"/min and could have gone higher but the screw was starting to bounce because it wasnt' attached to the gantry.
Anyway, I'm sure I'll need some help getting the Propeller to talk to the master board this weekend. If I can make the test board work, I'll order the whole set of tpics and another color of LED's and we should be set for the full production.
chaosgk, I dropped the matrix idea near the beginning of this thread. I only suggested it for the cost saving. Having a separate relay for each igniter is much more flexible.
I agree 8 relays per tpic is the way to go. Everything else fits nicely with that.
7 tpics with 56 bits/relays per slave board
8 output ports/distribution boards per slave
7 outputs per port/distribution board
No wasted bits on the tpics or unused relays, and 56 bits allows an 8 bit command and 56 bits of data to fit in 2 longs of prop ram so the software will be compact and tidy. The other commands can fit in one long and follow the same format of an 8 bit command with 24 bits of data.
You know, I am a jackass sometimes. [noparse]:)[/noparse]·
I clicked to show oldest first on the forum and it showed me the oldest post from the first page which happened to be another guy mentioning the matrix idea.
My bad.· Wow, do I feel dumb.·
It's one of those days, I was up late again and things aren't clicking right. ·
Comments
1 Prop development board connected to the master driver board.
8-10 slave boards (40-64 relays each)
70+ distribution boards to connect to the slave boards via cat 5 cable.
we are on a real limited budget for the electronics and development costs so paying a company for that many boards is out of the question unless it's like $1 each board.· Every place i've looked into has been at least $100 for one slave board to be printed and drilled.· I'd love to get all of them professionally made, but we are just a private/non profit group and don't have a lot to spend each year.
I'll still take help from anyone on designing the boards so I can print and etch·them myself. I am just about done with my cnc for all of the drilling so that will help and I have a bunch of friends willing to help solder the points and hardware.
We're also down to about a month before we can start building the pyro's themselves. We live in North Dakota and have had one hell of winter and can't build anything till I can kill the furnace in the shop for the summer and it needs to be warm enough outside to let powder dry and grind in the ball mills.
I'm also assuming you are at least 18????
making boards your self is great though making double sided boards can be difficult.
4pcb.com offers $600 off first order which depending on order size can be free.
if you are doing any of the layout in eagle I would be happy to help.
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Need to make your prop design easier or secure? Get a PropMod has crystal, eeprom, and programing header in a 40 pin dip 0.7" pitch module with uSD reader, and RTC options.
I have 15 drivers and receivers on the way from hong kong, they matched the ones we had spec'd earlier. I think I will be using dip sockets for most of the chips that will be on the boards, (ie drivers, receivers, and tpics). I still need to order the tpics and anothe color or LEDs for the relay status lights. Green=good ignitor, Red=active relay.
larger means dimmer but still works
voltage in-voltage diode
current desired
gives minimum resister value
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Need to make your prop design easier or secure? Get a PropMod has crystal, eeprom, and programing header in a 40 pin dip 0.7" pitch module with uSD reader, and RTC options.
(voltage in-voltage diode)*current desired
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Need to make your prop design easier or secure? Get a PropMod has crystal, eeprom, and programing header in a 40 pin dip 0.7" pitch module with uSD reader, and RTC options.
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·
you are providing 12mA to the led probably under max current but not necessary
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Need to make your prop design easier or secure? Get a PropMod has crystal, eeprom, and programing header in a 40 pin dip 0.7" pitch module with uSD reader, and RTC options.
The CNC is operational now, I have some cleanup to do on it and build a stand for it this week, but it cuts and is very accurate.· I have some tweaking to do with the X axis over long runs and really need to learn the software end of it.
I should be able to start drawing up the boards again.
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Need to make your prop design easier or secure? Get a PropMod has crystal, eeprom, and programing header in a 40 pin dip 0.7" pitch module with uSD reader, and RTC options.
Adding more TPICS to a board would complicate the software. I had planned on having commands that were one or two longs.
The time command would be 1 long consisting of an 8 bit command and a 24 bit time (in mSec from T0).
The fire command would be 2 longs consisting of an 8 bit command/slave number and 24 + 32 bits where a 1 bit would fire the corresponding relay/igniter.
Adding 3 more TPICS would mean adding a third long and using 24 of the 32 bits to control them. Much easier to stick to 7 TPICS, 56 relays per slave and add another slave if more than 448 relays are required. I planned on having a 4 bit slave address, allowing up to 16 slaves which would be 896 relays. Do you think you will need more than that? If so I can go to a 5 or 6 bit address allowing 32 or 64 slaves.
As far as the 20awg, I can bump that up to 18 or 16 easy enough. So do we want to go with 7 or 8 tpics per slave? I am thinking it will be 8 tpics per slave with 7 of the channels being used (7 wires per RJ45 for +24v and 1 wire for common).
TPIC 1 will receive bits 1 to 8, and will be connected to relays 1 to 8.
TPIC 2 will receive bits 9 to 16 and will be connected to relays 9 to 16, etc., etc. so TPIC 7 will receive bits 49 to 56.
RJ45-1 will be connected to relays 1 to 7
RJ45-2 will be connected to relays 8 to 14, etc., etc., so RJ45-8 will be connected to relays 50 to 56.
No problems. If I want to set off the device connected to relay 37 on slave 1 I clear all 56 bits, set bit 37 to 1, shift out the 56 data bits, and transfer the data to the output at the appropriate time.
Are you thinking the other way, just continue with moving the 8th one down each time.
First one will carry over 1, 2nd will carry over 2, 3rd will carry over 3 and so on until the end where the 8th will hold everything from the 7th tpic except #1?
On the master do you want 12 ports out or do you want to put 2 panels on for 16 or 24 ports. Keep in mind that each port will require a driver, and going beyond 16 drivers will require another address line. Best to lay the board out for as many drivers as you may want, although you only need to mount as many as you need on the board.
How do you want to connect them on the slaves? I am assuming one port for input so will it be either 8 for output, or distribute them more evenly (10x5 connections + 1x6 connections)?
Anyway, I have 15 drivers and receivers on the way so I think I will plan for that many on the board. 12 will get mounted in the panel of 12 ports and the other 3 will be aux with the drivers installed but the ports not put in place yet. I will probably just put a 8 pin header in for the other 3 ports.
I am not sure what you are getting at on the slaves for the 10x5 + 1x6 for connections.
I would expect to use one of the 12 ports for input and another 8 for output and have a couple that aren't used.
I'm not sure how it will work if I have to stack boards in the slaves. I may see if I can have a smaller board of tpics that all wire into a couple of 40 pin headers and connect those headers via ribbon to a relay board...... hmm. I'll have to look into that.
What I meant by 10x5 + 1x6 was that you have 12 ports, one port for input and 11 for output so if you wanted to use all the output ports you could have 5 outputs on 10 of the ports and 6 outputs on one port. I agree with you that it makes more sense to use one for input, eight for output, and leave three unused or used for something else.
I also agree that it may be better to have the relays on one board and the tpics on another. How big is the relay footprint?
For the Master:
The protoboard has 32 I/O pins. Four are used for programming and the eeprom, leaving 28 available. Five are used to send control signals to the slave leaving 23 available for selecting slaves and other uses. These five lines will need five resistors to go from 3.3V prop pins to 5.0V of the drivers.
For selecting slaves we have 2 choices. We can use one I/O line per slave which requires 15 lines with 15 resistors to go from 3.3V of the prop to 5.0V of the drivers. The other option is to use one or two logic chips to do the driver selection and would require 5 lines and 5 resistors (or possibly fewer) between the prop and the logic chips.
To anwer your question on the relays, I believe they are 5mm x 10mm.· pretty small.· It's not the question of fitting all of the relays on the board, it's the trace space I need for the relays. I know I can go pretty small on the traces that activate the relays, but the ones that drive the ignitor need to be pretty good size so fitting that many traces in a compact space is posing a slight space issue.
Post Edited (chaosgk) : 4/16/2009 6:22:00 PM GMT
The pyro racks will be based on multiples of 7 so we can run only 3 cables to a 21 shot rack vs 5 cables for the same rack if you catch my drift.
It's all comes down to efficiency on shooting day.· We hope to have everything completed at least a week before the 4th so on the 4th we can get up early in the morning, put all the racks in their places, plug cat 5 cables into all the jacks check for contenuity and relax for the rest of the day until dark.
I would actually like to be able to enjoy some time hanging with family and friends for once.
Again, thank you to everyone that is helping with this, I know I couldn't do any of this alone.
·
I completely get where you are coming from with the matrix idea, but I think in the long run, the 8 relays per tpic are the way to go.· I will be ordering 100 tpics so they are coming in at bulk price of $1.55 each I think, pretty good price off the regular $2.50 each.
I should have some time on sunday to start drawing up the PCB again and we'll see where that goes. I will do a small test one of maybe 8 or 16 relays with the receivers installed and see where we are at after that.
I had some trouble with my X axis of my new CNC that mostly have fixed.· I went from using 5/16th drive rod to 1/2".· What a difference.· I was limited to 18" travel/min with the 5/16th.· Testing last night with the 1/2", I was up to 75"/min and could have gone higher but the screw was starting to bounce because it wasnt' attached to the gantry.
Anyway, I'm sure I'll need some help getting the Propeller to talk to the master board this weekend. If I can make the test board work, I'll order the whole set of tpics and another color of LED's and we should be set for the full production.
·
I agree 8 relays per tpic is the way to go. Everything else fits nicely with that.
7 tpics with 56 bits/relays per slave board
8 output ports/distribution boards per slave
7 outputs per port/distribution board
No wasted bits on the tpics or unused relays, and 56 bits allows an 8 bit command and 56 bits of data to fit in 2 longs of prop ram so the software will be compact and tidy. The other commands can fit in one long and follow the same format of an 8 bit command with 24 bits of data.
I clicked to show oldest first on the forum and it showed me the oldest post from the first page which happened to be another guy mentioning the matrix idea.
My bad.· Wow, do I feel dumb.·
It's one of those days, I was up late again and things aren't clicking right.
·