Search found 8 matches

by achechin
22 Apr 2013, 10:00
Forum: Mindstorms Hardware
Topic: Electronic switch for external power
Replies: 4
Views: 4948

Re: Electronic switch for external power

All of these could also be driven from a sensor port using a PCF8574 - http://www.futurlec.com/Mini_PCF8574.shtml. h-g-t, thank you for the answer. Could you please explain how power could be driven from PCF8574? I have several PCF8574 sets from Mindsensors so could use one of them instead of Mini ...
by achechin
21 Apr 2013, 10:41
Forum: Mindstorms Hardware
Topic: Electronic switch for external power
Replies: 4
Views: 4948

Electronic switch for external power

Dear All! I am using Mindsensors 8 channel servo controller( http://mindsensors.com//index.php?module=pagemaster&PAGE_user_op=view_page&PAGE_id=93 ) to run multiple servos. It required external 6 Volt power and I am using Mindsensors 4AA Battery Holder with NXT Mount ( http://mindsensors.com//index....
by achechin
10 Jan 2013, 11:25
Forum: Mindstorms Hardware
Topic: Lifelites LED's with PCF8574
Replies: 11
Views: 11999

Re: Lifelites LED's with PCF8574

Gents, I assembled Mindsensors PCF8574 and its working ok. The only problem I realize after assembling is it size. To hide that plate required quite large area. So, the next step I am planning is to assemble custom PCF8574 and make it as small as possible. I found a simple solution in "Extreme NXT" ...
by achechin
08 Dec 2012, 07:18
Forum: Mindstorms Hardware
Topic: Lifelites LED's with PCF8574
Replies: 11
Views: 11999

Re: Lifelites LED's with PCF8574

Finally I bought couple mindsensors PCF8574 sets http://mindsensors.com/index.php?module=pagemaster&PAGE_user_op=view_page&PAGE_id=71 Now I have coupl e more questions about it. On PCB connector area, each item (ie 5 v) have two holes. Are they exactly the same and doubled for convinience? When shor...
by achechin
09 Nov 2012, 10:58
Forum: Mindstorms Hardware
Topic: Lifelites LED's with PCF8574
Replies: 11
Views: 11999

Re: Lifelites LED's with PCF8574

Thanks everyone for your help! Lifelites wired resisters into some LED's thats why regardless the color they all rated 3.2V.
by achechin
06 Nov 2012, 11:33
Forum: Mindstorms Hardware
Topic: Lifelites LED's with PCF8574
Replies: 11
Views: 11999

Re: Lifelites LED's with PCF8574

Update.

Lifelites helped me with socket type as well as provided LED parameters.
Could you please recommend me a resistor size and type (metal or carbon) for the following LED's:
3.2 V and 20 mA.

Am i right thinking about 120Ohm and 1/4 Watt?

Thanks and regards,
Alex
by achechin
04 Nov 2012, 09:44
Forum: Mindstorms Hardware
Topic: PCF8574 vs PCF8591
Replies: 2
Views: 3462

PCF8574 vs PCF8591

Really simply question which still isn't clear to me.

What is the difference between PCF8574 and PCF8591? Please show it on examples rather than tell that one is digital IO other one is analog.

Thanks in advance!
Alex
by achechin
04 Nov 2012, 03:46
Forum: Mindstorms Hardware
Topic: Lifelites LED's with PCF8574
Replies: 11
Views: 11999

Lifelites LED's with PCF8574

Dear All, I have a lot of LED's for LEGO from Lifelites ( http://lifelites.com/ ). Now would like to connect them to Mndsensor PCF8574. To make a device flexible I would like to solder on board female sockets like Lifelites use ( http://lifelites.com/products/133 ), rather than LED cables. Does anyo...