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485 data extraction
- Thread starter angryman
- Start date
MacGyverS2000
Electrical
Unless you provide more useful data about what you need to accomplish, I see this thread getting locked pretty quickly... so far it sounds like you want to reverse-engineer something that doesn't belong to you.
Dan - Owner
Dan - Owner
- Thread starter
- #3
MacGyverS2000
Electrical
Ah, that's useful info...
Disregarding for the moment that two master controllers would be bad (I'll leave that oen up to you to figure out), it's not a bad problem, per se. The "new" master controller (buttons) would use some addressing scheme that wouldn't interfere with data modules currently on the bus. The new "slaves" would understand the addressing scheme and do what they're told.
Your problems seem to be:
1) You want to do this with no code writing (probably impossible)
2) You'll have multiple masters on the line (doable, but you have to get them to work together... typically involves code, but can be done in hardware)
3) Slaves of one type cannot interfere with slaves of the other type (again, involves code)
Dan - Owner
Disregarding for the moment that two master controllers would be bad (I'll leave that oen up to you to figure out), it's not a bad problem, per se. The "new" master controller (buttons) would use some addressing scheme that wouldn't interfere with data modules currently on the bus. The new "slaves" would understand the addressing scheme and do what they're told.
Your problems seem to be:
1) You want to do this with no code writing (probably impossible)
2) You'll have multiple masters on the line (doable, but you have to get them to work together... typically involves code, but can be done in hardware)
3) Slaves of one type cannot interfere with slaves of the other type (again, involves code)
Dan - Owner
- Thread starter
- #5
Yes, that is what I was thinking...I figure I'm either gonna need a code writer(person) or a cheap protocol analyzer (is there such a thing?) or labview, which I'm pretty sure I could do it in, but we do not have labview....
I was approached with this challenge and really need to just verify that I'm not overlooking something simple...I think they are thinking there is some sort of blackbox out there that will allow this, but I cannot find it if so....
Thanks for your input...
I was approached with this challenge and really need to just verify that I'm not overlooking something simple...I think they are thinking there is some sort of blackbox out there that will allow this, but I cannot find it if so....
Thanks for your input...
Skogsgurra
Electrical
Perhaps it is time for you to do some code writing? It is not at all difficult. Kids do it. Have a look at a Basic Stamp or any other "stamp" type small computer. They come with a serial interface (RS232) that can easily be converted (only hardware) to RS485.
These stamps also have parallel I/O. Arrange the stamp to recieve the 485 commands and send them down the line - fully transparent. Then, write a simple code loop that tests the inputs and, if one of the push-buttons is activated, sends the corresponding command. Just do it! You will learn a lot. And you will probably have some fun, too!
A "basic" Basic Stamp won't cost you more than about USD 100. Perhaps less. Add power supply and level converters plus some I/O filters and you will end up with something like USD 200. Then, you may want to make a PCB out of it. That will take a lot more work - and still a couple of 100 dollars. But it can be done at a fairly low cost.
If you approach an engineering company with this, you can probably get it done under USD 2000. It all depends on what they already have in store.
Gunnar Englund
These stamps also have parallel I/O. Arrange the stamp to recieve the 485 commands and send them down the line - fully transparent. Then, write a simple code loop that tests the inputs and, if one of the push-buttons is activated, sends the corresponding command. Just do it! You will learn a lot. And you will probably have some fun, too!
A "basic" Basic Stamp won't cost you more than about USD 100. Perhaps less. Add power supply and level converters plus some I/O filters and you will end up with something like USD 200. Then, you may want to make a PCB out of it. That will take a lot more work - and still a couple of 100 dollars. But it can be done at a fairly low cost.
If you approach an engineering company with this, you can probably get it done under USD 2000. It all depends on what they already have in store.
Gunnar Englund
MacGyverS2000
Electrical
That sounds like a mini board Keith (itsmoked) would already have on hand, or at least one close enough to make a simple mod to for this application.
Dan - Owner
Dan - Owner
Skogsgurra
Electrical
Yes, I would think so. But now, we are close to the thin line: "Promoting, selling, recruiting and student posting
are not allowed in the forums"
Gunnar Englund
are not allowed in the forums"
Gunnar Englund
- Thread starter
- #9
time time time time
Skogsgurra
Electrical
Mark,
I know people that do such things in their spare time. It's called self-teaching...
Gunnar Englund
I know people that do such things in their spare time. It's called self-teaching...
Gunnar Englund
- Thread starter
- #11
Just remember one thing, RS485 is a hardware standard, not a software one. And even as a hardware standard, many are tagging RS485 systems some that are in fact doing RS422. Duplex instead of multidrop party line. So you may discover lots of things with this project. Fun things if you're not subject to a strict timeline, frustrating otherwise...
Haha, Thanks for the ahem.. cough.. plug Dan.
Sounds like a fun project angryman. A short one with an end in sight unlike some... As skogs sez it's a good little project for someone to "get their feet wet" using a small-off-the-shelf board. It could turn into much more for you opening your horizon a bit.
Here's a link to stamps:
Keith Cress
Flamin Systems, Inc.-
Sounds like a fun project angryman. A short one with an end in sight unlike some... As skogs sez it's a good little project for someone to "get their feet wet" using a small-off-the-shelf board. It could turn into much more for you opening your horizon a bit.
Here's a link to stamps:
Keith Cress
Flamin Systems, Inc.-
- Thread starter
- #14
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