External ADC

[rossw]

What is the earliest version code that will support the DS2450?
I found your post here that "the current version adds support for" but it didn't say what version it was!

I tried with 3.02.07 and the board would not start - gave a few blinks of the green LED, brought up the ethernet lights (even with no ethernet plugged in). Would do a DHCP request but then just sat and looked stupid for about 30 seconds, then repeated the whole thing again.

How about a list of features and board firmware so we can see just what will and won't work?
It irritates me no end every time I pull a board out, I never know quite what will and won't work on it, and they don't have any external marking as to what firmware they contain (not that that really helps without the feature list).

 

[fwd03]

I tried DS2450 before, the value is all over the places. That might be the reason Maxim-IC stopped making it.

 

[CAI_Support]

Ross,

The change log is online at:
http://www.cainetworks.com/products/webcontrol/webcontrol-changelog.html
The DS2450 support is in since 3.02.08. However, we are thinking removing it for two reasons. One is that DS2450 noise level is too high, very unstable. The other is that due to so much bad feedback Maxim-IC is no longer making it anymore.

 

[rossw]

Ross,

The change log is online at:
http://www.cainetwor...-changelog.html
The DS2450 support is in since 3.02.08. However, we are thinking removing it for two reasons. One is that DS2450 noise level is too high, very unstable. The other is that due to so much bad feedback Maxim-IC is no longer making it anymore.

So what you're saying is: I should not have bought these 4-channel 1-wire input devices because they're a dead-end path?
Are you considering another option? Currently, I use getall.cgi and parse the xml, but using input MUX means for additional channels my ONLY option will be to store secondary channels in var/ram, and since external reads could happen while I have the A/D inputs not on the "base" channel, I cannot rely on getting the right inputs, so ALL analog channels will need to be stored in local variables? Suddenly not looking so useful

 

[CAI_Support]

How many channels A/D do you need? We were thinking make DS2450 emulator chip before. Since WebControl32 will have 8 analog input anyway, that board might be your solution once it is ready.

 

[rossw]

How many channels A/D do you need? We were thinking make DS2450 emulator chip before. Since WebControl32 will have 8 analog input anyway, that board might be your solution once it is ready.

I have 6 PV arrays I need to measure current from and the bus voltage (nominally 105V, but varies from about 55 to 150V). Therefore, I need 7 channels at least, which I could just manage with 3 on the WC and 4 on the external DS2450.

I should think that a PIC chip with A/D in, could likely emulate a DS2450 without much cost or difficulty.

What resolution will the ADC be on the WC32 board?

 

[CAI_Support]

ADC in WebControl32 is also 10 bit hardware. We do oversample to about 12bit resolution.