Hi all,

I'm new to this forum. Seems to me the popular MCU around is PIC and Atmel . I'm doing NXP ARM7 now. Previously involved in Zilog and AMD. Would like to know if there's any ARM buddies there.

This post has been edited by sarcastizer: Aug 14 2009, 04:14 PM

Hi all,

Are home-made SMT PCBs feasible and recommended? Experience wise i have managed to make a few simple circuits on through hole PCB. Also, are common surface mount components (resistor/caps/555 timer/common ICs) easily available at Jalan Pasar or anywhere around KL? How much would they differ from the normal components?

This post has been edited by jubz: Aug 14 2009, 11:11 PM

Hi there,

I think PIC and Atmel are the most popular 8bit MCU worldwide.
Anyway I just started using PIC about 1 year ago when I started doing some freelance jobs and my primary concern then is functionality, availability and pricing which I think PIC did better than Atmel in Malaysia. I've only used the 16F family so far, been wanting to try the 18F family, had couple of those with USB lying around. Now I'm porting my code from assembly to C, using SourceBoost C compiler which seems to be pretty good and surprisingly cheap.

I've no experience or knowledge of ARM. Using ARC600 in my current full-time job but I've really no idea on the different between ARM and ARC. Previous job uses 8051 based MCU and before that in Zilog.


Erm.. what's the reason you wanted to use SMT over through-hole components?
I'm no expert in layout and PCB making, but I think for home-made PCB the minimum track clearance you can create are the main issue, which in turn creates a minimum pcb size you need to make. And making vias for double-sided pcb are very troublesome and unreliable.
Ain't sure about parts availability in Jalan Pasar, but I see from Farnell many SMT are cheaper than their through-hole counterparts.
I'm lazy to build pcb manually too

Yup i've been searching for it in here in any sales, all around Perlis and even Penang but still can't find it. Pls give me a pm if you're going and around how much would it cost. Thanks a lot.

Not familiar with ARM or ARC, not exactly a popular chip for hobbyist. How does it compare with other uC? Maybe will do a little google if had time. Sure like to play around with it, if the chip can be purchase over the counter.

I tried before DIY PCB etching up to 0.012", which turns out to be quite good, but that is for through-hole PCB. 0.010" should be achievable. Like what tgrrr say, aligning the pattern for the via can be a pain, well, unless you make the via thicker, so you have some tolerance in case it slips.

I haven't make my trip yet since my last post, been quite busy recently. If it is not urgent, I can check out for you. But you need to tell me exactly what chip are you looking for ah... How much is your budget? If it happen to be within your budget, you want me to quick grab for you?

just want 2 ask..does jalan pasar d only place to get electronics components around kl/selangor area? the more the merrier rite? im a 2nd year student of E&E so better grab some info on where to get parts now cz gonna be doin my project soon

Aurora, I think ARC is only for custom made IC, they buy the license and embed the ARC core inside their chip together with other stuffs. ARM I'm not sure.

Jalan Pasar is the most popular places in Kl, the whole road there is full of shops selling electric and electronics components.

Penang Island is Hondai (near Sg. Nibong Bus Stations), and Destiny (Near the Bayan Lepas KWSP office).
I know there's a Hondai in Penang Mainland, but ain't sure where is it.

Thanks for pointing out. I think ARM are quite high end chip, like use in mobile device. Anyway, you have any idea what IC/uC used to read camera module? I saw a cheap camera module in Sparkfun, and seems like 40mHz just barely able to read the camera module. I like to do something like wifi camera. Any suggestion? Maybe will get a cheap 2nd hand handphone with VGA camera, hack and see what they use inside.

e-fatty, nicotyne: I just saw this thread This guy has a lot of components for sale, maybe you can try ask him.

ARM MCU certainly will be an overkill if used for simple hobbyist project. ARM refers to the architecture layout inside the MCU itself. Various manufacturer are providing ARM microcontroller. NXP,Atmel and Freescale are providing it to name a few. I used ARM7 in my current work. I will be using PIC16F series for my future project.

Thanks for the response.

Am doing some schoolwork, would be interesting if we (me & my group mate) actually manage to make one. Plus we get to learn something additional. For our previous DIY PCBs, we used 0.015". We started with 0.010" but soon learnt that etching the board properly got difficult. Alignment problems were be reduced by concentrating most tracks on one side and using the other side for major tracks (ground,power,etc).

I was thinking if we used SMDs, the area occupied by components reduces and therefore we might be able to go single sided. Do correct me if i'm wrong..

Hi There, anyone can teach me how to make dc motor spin 2 direction? clockwise and anticlockwise 12vdc motor spin clockwise then spin anti closewise back

What i want is just any RS232-to-TTL Adapter to comm with my HyperTerminal.

According to some site that thing cost something around 5 dollar.

So Around RM 30 would be okay for me.

Its not that urgent and i'm in the middle of my sem so i don't think i'll be repairing it till hari raya or so cuz got a week for me to do it then.

So pls do buy it for me just when you stop by there.

Asked the fellow and he don't have it.

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Added on August 17, 2009, 8:41 pmHondai? What's Hondai. Sg.Nibong is not in penang island right?

This post has been edited by e-fatty: Aug 17 2009, 08:41 PM

Err.. never tried anything with video yet. How do you interface to the camera? Some high-speed serial or er.. analog AV signal?
I suppose it depends on how much information you're going to stream through your uC and whether your uC can handle it. Sounds like a lot of work I think you'll need a uC with DMA or multiple DMAs to help with the streaming, and maybe DSP for encoding/decoding. First thing I'd check is how much bandwidth is needed i.e. is 1Mbps transfer rate sufficient for your video quality?


Well if your circuitry is not too complex to require using double-sided layout, then yeah.
Else I'd rather use double-sided, the extra dimension can really makes your life much easier.


I think you need a H-bridge. Try google for it. Aurora probably can assist you in this better than me


You should have a circuitry drawn out first. Then you'll be able to tell what components you need. Like the Max232 usually needs some 1uF eCaps to work. And maybe a couple of pull up resistors to your hdd tx/rx line. Plus a vreg to power your max232.

Er, not the Nibong Tebal or something like that in the southern Pg area. Sg. Nibong Bus Station is the only bus station on Pg. Island.
I know there's a Hondai in mainlang Pg., will try to check with my friend.

e-fatty: it was mention in the link that hdd Vss is only +3.3v, max232 chip is rated for 4.5-5.5v (typ. 5v). You need to take a look at max3221, and the application note, usually it will show you few circuit example to how to connect the chip.

tgrrr: Honestly, I don't know what I'm looking for. Camera module usually transmit in i2c, with other information available by the reading the rest of the pins. I read the datasheet, seems like need to write down a lot of code if I were to use uC. In case there is already a better solution... like a specific chip or module My target is to at least able to read, say 50x50 line out of the entire resolution (VGA or higher). I'm working on a project similar to line-following robot, but can't use the typical close-range IR to scan the line, due to terrain constraint. VGA would worth a try. Let me know if you have other ideas

fantasy1989: to spin a motor the other way, just reverse the polarity (+ve connect to -ve, and -ve connect to +ve). If you want better control, can try H-bridge circuit. H-bridge has the advantage of speed control and brake. To design H-bridge circuit, first need to know what motor you use, and what is the motor load (what the motor is use for). You can read up in wikipedia to understand the basic of H-bridge. Let us know what the motor is used for, we'll suggest a better way to that. Cheers

ok ..thank you for the motor


anyone can tell me ...where to find this sensor i search some component shop ..tak ada ><! ...this call micro optical sensor right?

and anyone can teach me how to use HB2E relay? newbie on electronic
HB2E-DC5V

thank a lot ><

This post has been edited by fantasy1989: Aug 20 2009, 02:09 AM


Attached File(s)
 PZ2_series.pdf ( 580.5k ) Number of downloads: 9
 HB2E_DC12V.pdf ( 135.03k ) Number of downloads: 9

This sensor look kinda expensive, got water-prove somemore, want to install outdoor is it? Maybe you can try Jalan Pasar, try those shop that sell light, alarm. They may not have the specific model, but if you tell them what is your application, usually they can recommend you the alternative. But this only apply for manufactured parts

HB2E-DC5V, pin 3 and 14 are your input, give it a 5v supply and the relay will engage.
When engage, pin 8 and 2 will short, (aka connected), and pin 9 and 15 will short also.
When disengage, pin 8 and 1 will short, and pin 9 and 16 will short.
Usually this type of relay are used when you have 3 different circuit that run on different voltage supply. i.e., your switching supply run on 5v, and you need to use it to switch on a 12v circuit (pin 8 and 2, or 1) and another 24v circuit (pin 9 and 15, or 16).

Well 50x50 line x 1 char (assuming 7x11 size char) == 192500 pixels per image. I'm assuming it's a black&white only image.
Multiply by say 15fps, you'll need to stream through 2887500 pixels per second.
The raw data transfer would be ~360kbps which is sufficient for I2C (usually limited @ 400kbps).
With some encoder chip with good compression, maybe you can achieve higher video quality using the same amount of bandwidth, though I'm just purely guessing about this part and your uC need to decode the data.

Now the question is, are you going to do image processing in your uC, or just stream these data out wirelessly?
Processing data @ 360kbps is a lot of work. You'll probably need some hardware support i.e. some DSP engine.
Wireless transfer @ 400kbps is also rather high.

I don't really know well in building my own circuit.
What I wanted is the whole chip as in the guide or something similar to it that can get the job done.

Well if you know the address of electronic shops in penang pls do tell ne,


Won't the MAX232 work with 3.3V?
Cuz i can get 3.3V from the power supply of my PC.

And according to the guide it doesn't say anything about building any circuit.
isn't it just as simple as get the RS232 to TTL chip and connect all the wires?

Pls explain.

Does anyone know what kinda chip is / equivalents for MAXIM C78091? Tried googling but I can't seem to find the datasheet for it.

i just require one sensor to connect with pc and sent signal to pc ..like door open and close ..just for my project ..any sensor recommend?


thank for the info about relay