Ambitious Video Security System

**RetroPlayer** · 01-13-2007, 12:43 AM

I received the quad today. Where to start? Well, first of all, the auction listing was VERY deceptive! The unit sent does not include alarm inputs, relay outputs, or an RS232C interface. It does not support 4/8 cameras. The SERIES of this model does, but this one is the bottom of the line. I have emailed the seller with my displeasure. This is the item and the seller:
http://cgi.ebay.com/ws/eBayISAPI.dll...m=150078970527

Now, with that out of the way. It is actually a pretty nice unit. I hooked it up and played around with the menu a little bit. It has the menu choices for the features it does not include, so I thought I would crack it open and see if I could add them.

There are two main ICs inside. One is a techwellinc TW2824Q video mux controller. This chip has a bunch of really cool features, some of which are not being used or not being used to full advantage. Unfortunately, I didn't find a datasheet for this part, just a brochure so no idea how to hack it yet.

The MCU in it is a SM5964, which is an 8052 based micro with 36 I/O lines, UART, and three timer/counters. It looks like there is plenty of information about this chip online. It has 64K of flash memory and 1K of RAM.

Also on board is what I believe is a 16MB SRAM, probably used for the freeze frame function.

It has a battery backed real-time clock, buzzer for keypress/video loss alarm (which will be removed!)

It does not look like the MCU UART (serial port) is being implemented on the board, though I bet if I tap into it, it will work (it appears that the same firmware is being used for all models.) There are also several port pins on the MCU that look like they are not connected. These are most likely the alarm inputs and outputs.

Anyway, it looks hackable. It is pretty small, but maybe not small enough for what I have in mind. If I get brave enough, I may take some ideas from this quad to build my own. The technology used looks deceptively simple.

**mugurg** · 01-13-2007, 04:06 AM

Sorry to ask... What is this unit actualy do? It is just a video mixer in not so many words?

**RetroPlayer** · 01-13-2007, 12:54 PM

Video multiplexer. It displays multiple cameras on the screen at once, or it can sequence between them.

**mugurg** · 01-13-2007, 12:58 PM

and will split the screen in 4, displaying all cameras as quarters of the screen each?

**RetroPlayer** · 01-13-2007, 09:42 PM

Yeah, that is ONE of the modes. Either 4 split screen, 2 split screen, full screen auto-sequencing mode, or 1 camera at a time full screen, and this quad has another cool and useful feature: Picture-in-Picture.

You set one camera for full screen, and up to 2 other cameras in smaller windows that you can position around on the screen. So, you get a big view of the main camera while still monitoring 2 other cameras.

The quad is a color model.

**mugurg** · 01-14-2007, 04:50 AM

I need to buy one for the damn PIP. definitely.

**RetroPlayer** · 01-14-2007, 05:26 PM

I have begun prototyping what parts of the circuit I can and had a "DOH" moment! The latching relays I am using for power are DPDT, which means that for the cameras, I can switch power and video with a single relay. Of course, that isn't the cleanest way to do it, but it should work satifactory. The advantage being less circuitry and fewer I/Os. The disadvantage is that it locks me into using only one camera at a time. I guess the decision maker will be whether I can fit the quad into the case. I would rather use that.

**mugurg** · 01-14-2007, 06:05 PM

that will work for mee too. although i will have 8 outputs and 5 digital inputs, this solution will work for me as well.

**RetroPlayer** · 01-18-2007, 02:28 AM

So, my car got side swiped last night or early Wednesday. It triggered my warn away, but not the full alarm. The ****** drove off after doing it. I have no idea who it was. Boy that camera system would've been nice!

Sigh....still no DVR. If anyone reading this decides to buy one, get it from the asia-products website. Don't buy it on eBay. The seller I bought mine from is the only one selling it on eBay right now. The item was purchased on the 29th of December.

The only positive is that you really can't see the damage that well. Other than the three 'tamper' chirps telling me someone had been messing with the car, I couldn't tell anything was wrong until I went to open my door. A small piece of the chrome trim was busted near the door hinge and there is a small but sharp crease in the fender which pushed it into my door. It is interfering with the opening of the door. Can't see any paint chipping. Might be able to pop it back and straighten it, then replace the door trim.

Then again I might just get my insurance company to get it fixed. I didn't see a point in calling the police and I needed to get to work. Hopefully, they won't require a police report.

Anyway, the point of this post is that I am even more upset now that the parts to finish this up have not arrived (not that I would have had everything done and installed by now.) It did make me realize that I should make sure to tap into the 'warn away' part of the alarm. Seems obvious now, but I hadn't really thought about that before.