Must-haves for EASY DIY controller?

[der_wille_zur_macht]

Zen,

Any 10uF electrolytic cap will work for any of the 10uF parts on the board. Same with the 47uF caps. Other than the charge cap on the 7660, the values aren't really even likely very critical.

blckizzz,

That's an interesting approach but not really compatible (or required) with the direction we're going here. That shield is basically just a pin breakout to make the sensors more convenient - it would be easy to plug the phidget sensors into the board we've designed with a little bit of trivial wiring, if you wanted to use them. My only real big beef with their approach is that their products aren't released under an open-source friendly license.

 

[ZenMastr1968]

Ok, thanks DWZM...C10 is the way it is (SMT) purely because of board placement(that's what I'm imagining)??

That was the last part I needed to track down, so I'll put that mouser order through today. The rest of the chips are on order from DigiKey, a two pack of Ethernet jacks were supposedly sent air mail from the far east last week, and my meter came yesterday...

I should be breadboarding maybe next week.

 

[ZenMastr1968]

Question: I just want to make sure I'm looking at things right - in Eagle, on the board layout, is the 16 pin header between J1 and X1 on the right hand side the breakout for the display?? I don't see it labeled....

If I'm on the right track, then I assume pin16 is just on the ground plane? and pin15 looks like backlight positive and that is routed to D8 (digital output 8)??? So that's the pin you were talking about having it hard wired to? And so D08 is not a PWM pin....I'm beginning to see the bigger picture.

Most of the signal pins from that header are going to U5 which I believe you said is the controller for the LCD...

 

[der_wille_zur_macht]

OH C10 - yeah, that;s a little more specific, too. It needs to be ceramic. The ENC ethernet chip has an internal voltage regulator (for 2.5v I think?) and that cap is related to that function. Check the datasheet for the range of acceptable values. I made it an SMT package because it's easier to find cheap ceramics in SMT that size, rather than through hole. So if you are breadboarding then you can probably use a through hole part, just check the ENC's datasheet to make sure what you get is acceptable.

You are correct about the 16 pin header on the right side of the board, that's for the LCD.

 

[der_wille_zur_macht]

Oh. I have another request of the group following this thread. I really liked the Hydra name we came up with. I need another, similar name for a related project soon to be unveiled. So throw me some other nice-sounding water-related names from mythology or real life! I came up with an Irish Gaelic sea-creature name I like but its pronunciation is probably hard/jarring to non-speaking ears. . .

 

[ZenMastr1968]

I got my air mail package with 2 Ethernet jacks from hong kong yesterday.... One more piece down.

 

[ZenMastr1968]

OH C10 - yeah, that;s a little more specific, too. It needs to be ceramic. The ENC ethernet chip has an internal voltage regulator (for 2.5v I think?) and that cap is related to that function. Check the datasheet for the range of acceptable values. I made it an SMT package because it's easier to find cheap ceramics in SMT that size, rather than through hole. So if you are breadboarding then you can probably use a through hole part, just check the ENC's datasheet to make sure what you get is acceptable.

The DigiKey datasheet for the ethernet chip http://ww1.microchip.com/downloads/en/DeviceDoc/39662c.pdf says this about pin Vcap

2.5V output from internal regulator. A low Equivalent Series Resistance (ESR)
capacitor, with a typical value of 10 mF and a minimum value of 1 mF to
ground, must be placed on this pin.

and then I found this in the magnetics section

Some of the device's digital logic operates at a nominal
2.5V. An on-chip voltage regulator is incorporated to
generate this voltage. The only external component
required is an external filter capacitor, connected from
VCAP to ground. The capacitor must have low equivalent
series resistance (ESR), with a typical value of
10 μF, and a minimum value of 1 μF. The internal
regulator is not designed to drive external loads.

I don't see anything that says it has to be ceramic - is that implied by some of the definitions? I found a low ESR Electrolytic cap on Mouser's site that's 10uf and rated at 50V - is that not a good alternative?? http://www.mouser.com/ProductDetail...=sGAEpiMZZMtZ1n0r9vR22Z8b58wL7NwvrZ/6mAwXIFg=

 

[der_wille_zur_macht]

It'll probably work, give it a shot. Though, the 50v rating is pretty huge compared to the 2.5v load!

If you search "ENC28J60 Arduino" you'll find schematics for two or three popular open source Ethernet shields using this chip, you can check your design against the parts spec'd in those.

 

[ZenMastr1968]

Oh. I have another request of the group following this thread. I really liked the Hydra name we came up with. I need another, similar name for a related project soon to be unveiled. So throw me some other nice-sounding water-related names from mythology or real life! I came up with an Irish Gaelic sea-creature name I like but its pronunciation is probably hard/jarring to non-speaking ears. . .

Atlantis, Poseidon, Trident, Manta - kind of hard not knowing anything about it...

 

[TheFishMan65]

I think we kind of need to know what it is going to do to give it a proper name. I liked Hydra because it was going to be a monster to program so it works for everyone.

 

[terahz]

Oh. I have another request of the group following this thread. I really liked the Hydra name we came up with. I need another, similar name for a related project soon to be unveiled. So throw me some other nice-sounding water-related names from mythology or real life! I came up with an Irish Gaelic sea-creature name I like but its pronunciation is probably hard/jarring to non-speaking ears. . .

Well if it is related to Hydra, depending in what way you can use Hydra's "parents" names: Typhon(Typhoeus) and Echidna. Here are some water mythology creatures: http://www.lenntech.com/water-mythology.htm

 

[ZenMastr1968]

It'll probably work, give it a shot. Though, the 50v rating is pretty huge compared to the 2.5v load!

If you search "ENC28J60 Arduino" you'll find schematics for two or three popular open source Ethernet shields using this chip, you can check your design against the parts spec'd in those.

Just trying to find something they have in stock...that was the first one i've found. Is it a case where it will either work or not - or it will degrade the circuit over time??

 

[der_wille_zur_macht]

terahz, you get +1 for naming skillz again.

Zen, I'm not enough of an EE to tell you exactly HOW it would not work, hence, try it and see - worst case, if you get erratic behavior, swap a different cap in an see if it changes. At worst you're out ten cents or whatever.

 

[ZenMastr1968]

Zen, I'm not enough of an EE to tell you exactly HOW it would not work, hence, try it and see - worst case, if you get erratic behavior, swap a different cap in an see if it changes. At worst you're out ten cents or whatever.

Just thought I'd ask...

 

[roshan_samuel]

Just thought I'd ask...

You will not degrade the oscillator over time. However, you might see the crystal not oscillate, or, the crystal will stop oscillating when you look at it funny. Very frustrating, but no permanent harm done. A good way is to find the manufacturer of the crystal and use the exact caps they recommend. Even better, go to Microchip's web site and find their set up and use it exactly.
VREG cap will also not degrade the device, but a bad cap will send its control loop into a tizzy. Worst case, you will see repeated resets and Brown out events on the device as the internal voltage drops below 2.25v.

 

[ZenMastr1968]

You will not degrade the oscillator over time. However, you might see the crystal not oscillate, or, the crystal will stop oscillating when you look at it funny. Very frustrating, but no permanent harm done. A good way is to find the manufacturer of the crystal and use the exact caps they recommend. Even better, go to Microchip's web site and find their set up and use it exactly.
VREG cap will also not degrade the device, but a bad cap will send its control loop into a tizzy. Worst case, you will see repeated resets and Brown out events on the device as the internal voltage drops below 2.25v.

Ok, thanks for the info..... I'll dig a little deeper. EAR seems to be a not easily quantified measurement. I'll check microchip's site and see what I can find. One ethernet shield design I saw used a tantilium cap there.

My mouser order is supposed to arrive Monday and my digikey order is also on it's way....can't wait to start piecing this together.

 

[ZenMastr1968]

EAR seems to be a not easily quantified measurement.

ehhhhh, ESR...... Stupid iPhone autocorrect.

 

[Obi-dad]

... Stupid iPhone autocorrect.

I love my iPhone - but that autocorrect function can drive me nuts if I don't pay attention to it, comes out with some bizarre stuff.

 

[zachtos]

Hi, I thought about making a controller of sorts for my reef. I am extremely familiar with the arduino because I created IRcombat (modern laser tag system). I would have to agree with Beananmial on the first page about seperate controllers for each device. There are way too many failure points when doing this work yourself. I was just going to design a monitoring system, and have seperate controllers. That is much safer. Let me know if you want any code help (or go to the arduino forums).

 

[ZenMastr1968]

I love my iPhone - but that autocorrect function can drive me nuts if I don't pay attention to it, comes out with some bizarre stuff.

I thought it was an oversized iPod when my wife wanted one...but it's become quite invaluable to me :fun4:

Back on topic.... I got my DigiKey order today - ethernet chips and other items either not in stock or otherwise not carried by Mouser, now in hand. I also got my replacement RBBB board the other day and have transplanted all the components and have my test bed back in operation again. Just played with a sketch to put the backlight on a pwm pin - very cool!!!!

Confirmed that my Mouser order is in route and should be here on Monday...