Show Posts
Pages: [1] 2 3
1  Using Arduino / Programming Questions / Re: Arduino as a Telnet CLient on: July 19, 2011, 04:14:21 am
Yeah, that's definitely not right. I'd say that's your problem, alright.
2  Using Arduino / Programming Questions / Re: Arduino as a Telnet CLient on: July 18, 2011, 02:37:45 pm
The W5100 has a lot of pins connected to ground, I suspect that's what you're seeing. This is my (perfectly functional) Etherten:

3  Using Arduino / Programming Questions / Re: Arduino as a Telnet CLient on: July 18, 2011, 04:07:18 am
nothing works for me. I just tried the other examples and it seems as if the Arduino doesn't connect to my network. Neither the TX/RX/LINK LEDS on the board or the leds on my switch or router light up when I connect it. Maybe it is defect???? I just emailed the vendor to see if I can get a new one.

That's a layer-1 problem - you don't have an Ethernet link, and there's no point trying anything in sketches until you do.

How are you powering the Arduino and Ethernet shield? If it's USB powered, the voltage may not be high enough. I have a Freetronics Etherten which needs to be powered from an external 12V PSU for the Ethernet chip to initialise properly.
4  Using Arduino / General Electronics / Re: Soldering wires to pin-headers - am I just heavy-handed? on: July 12, 2011, 05:52:45 am
I've done something similar by soldering the pin headers into small pieces of stripboard, and soldering the wires onto the other end of the strips. Not pretty, but solves the overheating pin problem and is as solid as I could ask for.
5  Using Arduino / Programming Questions / Re: Arduino as a Telnet CLient on: July 10, 2011, 05:07:17 pm

Problem could be the subnetmask; as you use an 10.x.x.x network, the netmask should be 255.0.0.0 iso 255.255.255.0 (Class A network IIRC )...

CIDR networks obsoleted class A networks a very long time ago. Very, very few people who use 10.x networks still use the entire 10.0/8 as a single broadcast domain.
6  Using Arduino / Project Guidance / Re: Pro Mini + Ethernet on: July 10, 2011, 09:24:08 am
I actually need to check that because I'm not sure how the voltage is set coming from the PoE switch but I know it can vary based on the device.

If it's an 802.3af-compliant PoE switch, it's 48V, but it won't supply power to just anything. You need a PD circuit to let the switch know that there's a compliant device at the receiving end before the switch will attempt to supply full power.

You either need something like this, or make something equivalent from the 802.3af spec.
7  Using Arduino / Project Guidance / Re: First project (USB Connected Receipt Printer) on: July 08, 2011, 06:18:03 am
If the printer uses the USB port for serial comms, the USB host shield should work.
8  Using Arduino / General Electronics / Re: Voltage regulator or DC/DC converter on: July 07, 2011, 11:49:58 am
Yes, talking about 48V positive ground, which basically means -48V common mode. I've gotten around the grounding problem by using fully-isolated DC/DC converters, which allow me to connect the positive ground of the power supply to the negative ground of the Arduino without any problems.

That's an edge case anyway, and I don't mind forking out for the isolated DC/DCs in those situations. The +24V is the most common setup.
9  Using Arduino / General Electronics / Re: Voltage regulator or DC/DC converter on: July 07, 2011, 08:29:53 am
I'm not badly stuck for space. Price isn't the biggest obstacle, but it's always good to keep costs down.

I'll need the same basic board design to handle 24V, 48V and -48V supplies, either directly plugged in or through PoE. I might also need a 12V version. Rather than re-design the entire circuit around the different PSU requirements, I've designed it with a "daughterboard" arrangement. The individual  daughterboards take whatever supply voltage they're designed for, and output +5VDC to power the mainboard as well as an output scaled in the 0-5V range to represent the actual supply voltage (the whole point of this circuit is to monitor the parameters of the power supply).

The daughterboard is 1.2" by 0.9", so there's a little room to play with. The input and output supply pins are arranged at 0.1" spacing so I'll be able to mock up daughterboards on stripboard and test various components before committing to a PCB layout.

As for power consumption, I'll be driving an Atmega328 and a W5100 with a number of fairly low brightness SMT LEDs and   (optionally) a 16x2 LCD without backlight. I think I'd rather have the headroom of a full amp available.
10  Using Arduino / Programming Questions / Re: 1st time and can use a lil help on: July 06, 2011, 04:04:26 am
1st, you've given the value 13 to "drain" so it isn't going to be equal to zero anytime soon
It's worse than that (he's dead, Jim!):
Code:
const int  drain  = 13;
...
int drain =  Low;
11  Using Arduino / Programming Questions / Re: programming question on loop on: July 06, 2011, 03:57:15 am
I propose that Arduino C (or all C) be changed from tomorrow onwards to not require semicolons. In fact, I’d go so far as to say that Arduino C should be changed to Arduino Ruby. Then I’d be happy.
Excellent idea. Now all you have to do is write a compiler that generates AVR machine code from Ruby. Then lots of people will be happy.

While you're at it, could you throw in a Python compiler for me? Ta.
12  Using Arduino / Microcontrollers / Re: Moving on from prototyping on: July 05, 2011, 03:05:01 am
I've designed for a minimum size of 0805. I've managed to assemble a board with some 0603 components, but it was fiddly.

PCB-Pool are including a free stencil with each board design, which is nice - but is solder paste really useful if I'll be hand-soldering?
13  Using Arduino / Microcontrollers / Re: Moving on from prototyping on: July 04, 2011, 02:55:39 pm
Thanks for all the help. I've taken the schematics of Marc Alexander's EtherTen as a starting point, removed all the bits I don't need, replaced some of the components with parts I can more easily source, and redesigned the board layout from scratch. I've ordered PCBs from Beta Layout's PCB-Pool service, and I've been practicing my SMT soldering techniques.

I'll report back when I have the first prototype built.
14  Using Arduino / Programming Questions / Re: LCD.print to 3 decimal places on: July 04, 2011, 02:10:57 pm
Code:
lcd.print(ch1.realPower / 1000.0, 3)

The pedant in me wishes you'd use "kW" and "W" instead of "KW" and "Watts". smiley
15  Using Arduino / Programming Questions / Re: brand new to arduino on: July 04, 2011, 01:57:57 pm
The reason you put 'void' isn't to help the compiler, it's to help whoever is reading/using your code.  
It's both. If you declare a function as "void" and try to return a value, the compiler will catch the error.

Quote
Let's say I have the following method declared (without void):
Code:
OrderAPizza(char *pizza, int numToppings);
That's not valid ISO C++, according to my compiler - it requires a type declaration for the function.
Pages: [1] 2 3