ic.. Sensing between one IR transmitter transmitting and one IR receiver. Yup, parallel port should be able to do that.

Which circuit? The IR sensor or the communication with PC? Frankly, I have neither. it depends on which IR sensor, environment, controller.... Assuming fantasy1989 already had the circuit, I'm just stating the possibility of interfacing it with PC via parallel port.

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Added on August 31, 2009, 11:00 pmNot it the mood of googling... I'm sure there are tons of example

This post has been edited by Aurora: Aug 31 2009, 11:00 PM

Which infrared sensor you plan to use? Mind to post the datasheet so I can have a look?

azmax100, check your inbox. I sent you a PM about trading arduino with ICD2 LE. Let me know if you are interested. Thanks.

You can use any Lipo battery in the market, provided that it is rated for 3.7v. Lipo single cell voltage is 3.7v, that means there is only a handful of lipo battery with voltage of 3.7v, 7.4v, 11.1v etc, so don't worry if you get an off-spec battery.

The mAh is the capacity, the higher the number, the longer it can be put in service and vice-versa. You application probably drain only a few mA, other lipo specification is not important. If you can't find 1550mAh, you can use any rating, it won't affect your device.

So, you can just go to any handphone or camera shop, and show them the battery and say you want the battery which has the exact same size.

One last thing, all single cell lipo after fully charge is rated at 4.2v, therefore you may find certain lipo battery rated at 4.2v, instead of 3.7v. Don't worry, you can use it. Your device would automatically cut-off the charging when it reach the appropriate voltage.

This post has been edited by Aurora: Sep 27 2009, 01:03 PM

To properly charge a Lipo, it need a built-in charger circuit, which monitor the peak voltage. Charging lipo without proper monitoring is extremely dangerous, it may cause fire and explosion. And because it monitor peak voltage, they automatically cutoff when it reach peak voltage. It's safe to say that you may charge any mAh lipo, provided they have the same voltage rating. Normally the only concern for Lipo charging of the same voltage is its charging ampere. For your device, it should be relatively low, USB support relatively small current. USB devices with battery are normally smart charging circuit, not time-counter circuit. This is due to reason that the design take into account of frequent and inconsistent plug and play of USB device, hence the circuit need to be smart.

I forget to mention that you can get it from any RC store (as tgrrr point out). You can try asking in RC forum. As far I know, lipo can be custom made, rcsmart do offer custom made size and capacity, but with condition of minimum order of 5, I think. Not that I encourage you to customize ur battery , but they have more selection and you can get it from them. Another great site is HobbyKing. HK-base company, relatively cheap courier delivery cost.

You can try instructables, or try Jalan Pasar, I think I saw a kit or something similar, with LCD, temperature sensor, cooling fan. It's either by cytron or bizchip. With a bit tweak, you can interface with PC via DB-9 (or RS232). If you want a complete solution, I can do it for you, with a small price.

This post has been edited by Aurora: Oct 1 2009, 11:16 PM

As a pastime hobby, seeking personal satisfaction.

Shall we organise a TT?

"Teh Tarik" session Meaning a social gathering.

1) My inspiration mostly come from walking robot..
2) mostly microcontroller-base project. Currently working on legged robot

This post has been edited by Aurora: Oct 7 2009, 10:43 PM

I'm working on a multi-leg robot, not biped. Biped has limited room for creative motion, mainly due to stability issue. Commercialize/hobbyist unit is not up to the standard yet (at least not mine ).

For CNC-base design, have you already figure out the mechanism to transfer the rotation motion to linear motion? CNC machine normally use wormgear and rack, has high torque output, but at the expense of low speed. And depends on your load, you maybe able to use Tachus42 3 Axis Board, with some modification on the IC to suit your motor.

pminmo has several link to free software. These software has already pre-scripted communicate protocol with the board via parallel port. If you want to write your own program, maybe you need to get it from the author how the protocol works, or maybe reverse engineer yourself.

We (myself and tgrrr) are actually looking for small project for pasttime and some side income. Depends on your requirement, urgency, and to what extend, we could help you, at a reasonable price.

Just post it. But my asm knowledge is very limited.

fantasy1989: parallel port respond on +5v. For your case, if your switching is slow and time critical, you can use a transistor circuit, or op-amp circuit. If it is time-critical, then you need to get those TTL chip. Be careful when playing with parallel port, if you apply the wrong voltage or current, it may smoke your motherboard!

rokiroad: I found the solution already, in fact had my PCB board done. Speaker amplification, try this. Do look up for LM386 datasheet and application note for more info.

Hi Chein, what kind of project you have in mind? I'm using PIC (aka microchip product) because there are plenty of guidelines, code examples in books and www. Some of the most used and cheapest uC is PIC16F84A and PIC16F877A.

Atmel has a slightly different architecture, and able to execute more instructions per second. But to me, it's just the same. There are plenty of guides for Atmel as well. The most used Atmega16, 32 and 168.

Atmel has slightly better advantage in terms of coding. It come with a free C compiler. While Microchip free C compiler has some limitation, otherwise user need to purchase the unrestricted C compiler. Otherwise, if you are familiar with assembly code, both also support it.

Arduino (based on Atmel uC) is getting more attention recently, because it provide a simple board that allow user to connect to their PC, program it (in C), and execute the code. Very good for beginner.

Arduino is a complete solution. It comes with an Atmel uC sitting on a prototype board with a lot of pin out, and a usb connection to PC. So just plug into the USB, run the compiler, write your code, program it. The limitation on Arduino is that it pretty much seal the type of Atmel uC, so you get only that amount of pin, functions, and program space and RAM.

Then connect the pinout on the board to LED, siren, sensor etc. I think you can check with Azman, he hang around this thread earlier.

For Microchip, get those ICP (In-Circuit Programmer) type. it's program via 2-pin only, and standard power and ground connection. I'm using it and it's very easy. But the programmer is quite expensive la. Cheapest around RM200. Or you can get those local assembly third party programmer, I think it cost around RM100, with smaller number of supported uC.

For Atmel, I haven't seen their programmer in Malaysia.

I think Arduino is best for starter, Microchip and Arduino is more suitable if you have plan to move on to intermediate and advance level.

The most basic project you can do is LED related project, like trying variety of blink, dimming, etc. Most books, sites will recommend LED blink project.

The best place to look for is Jalan Pasar, KL. I think most DIY user don't mask their PCB board. I know I don't.

Those are industrial wire stripper. You can find a lot of those from different manufacturer. For electronic goodies, check Jalan Pasar, KL. Or check out ace hardware.

For cheaper unbranded stuff, you can check your local hardware shop, those big one. They might carry few.

I use this, made in china, serve me very well so far.



This post has been edited by Aurora: May 30 2010, 07:32 PM

Erm, I'm not familiar with any brand though. But all are pretty standard. You can spot the quality almost immediately when you held it.

Buck controller can get at the famous Jalan Pasar, KL....!!!!