[quote author="anachrocomputer"]Greeeg, do you mind if I post the modified version here?[/quote]
Go ahead I don't mind. My original code was to help people start up with the displays, If you've improved it I'm sure others will benefit :D
I only used the larger MSP so that I'd have access to the specialized Peripheral ICs of the device: PWM/Timer capture input/Clk out, etc. combine that with a screen and you have a neat testing platform.
[quote author="bseishen"]Has anyone found the .6mm FPC/FFC connector by chance?[/quote]
The FFC on my displays is designed to be soldered directly onto a PCB. i.e. it has "vias" on the exposed FFC pads that allow the solder to flow through between the board and the FFC. I'm not sure how well this would work in a connector, however if your display does not have these "vias" then a connector would probably be wise.
You've placed single headers underneath the LCD footprint, I assume these are mainly for testing and debugging, but why not place then out from underneath the LCD. Might save you some trouble down the line.
The LM358 might not work well with lower voltage input, eg testing a 3v supply with 1A a rail to rail would be more expensive, but would probably help immensely. Microchip have a bunch of really cheap 5v ones.
Not sure why that source trace has to be so large coming back from the FET. All the current should be going through the resistor. Unless it's just to reduce resistance...
1 button really restricts what this device can do. Next revision I might add another button or maybe an accelerometer, I do have a pile of MMA7455's they are dirt cheap. :D
I Just check my DIY bus pirate PCB and I can see the pin marks on the pads, no marks like that are visible on my boards. I wonder what ITead would say if I quizzed them about it.
Interesting how the PCB fab does %50 and then ITead does the other %50. Since none of my board had any visible indications of e-test. (no texta mark, no tiny pin marks on the SMD pads) I just wonder how ITead knows which PCBs the factory has tested and and which one they have left to ITead.
Quick google turned up a review by Dave Jone from the EEVblog.com He always takes apart his products during reviews.
Skip to ~4min to see the insides. Looks like you're in luck a nice transformer in there. If you'll be able to switch terminals or need to replace the whole transformer, well, you'll probably need to take a closer look when you get yours.
You really should wait until you've got it and open it up to see how it uses the mains input. If it's straight into a transformer you're inluck.
However I recently opened my cheapo soldering iron and it did some kind of wizardry with some caps and a fet/triac/TO-220 package to switch the 240v directly. The sad news is Transformers are expensive so they're often replaced with cheaper methods.
One method for getting 240v is to use an inverter (12v -> 240v). but these get expensive as you start to increase their wattage. When you get it do you think you could take a few pictures of the insides so we can see what you're dealing with?
This is the basic connection I'm using to test out the display. The MSP430 has an inbuilt USI module but this software driven routine should be easier to port to any micro you want. [attachment=1] Here is some simple code. Designed for the MSP430 but should be easy to port to anything. just chage the P2OUT/DIR to your particular micro's port control regs.
Some Initial test show up ~200µA @ 3.6v on the VDD and VDDI (Analog and digital voltages) LED backlight is a single LED so it also runs on the same 3.6v line consuming about 22mA with no external resistor. With a small series resistor consumption can be brought down to 8mA with minimal difference in visible brightness. Probably safer with the resistor.
I have some really basic example code that prints strings to the display. (If anyone has one of these and is stumped for how to get it to work.)
Edit: I have found this page. it features an eagle footprint for the display along with some example code, Downside...It's in Russian :P
These are Displays from ebay are small B/W displays from the nokia 1202 and a few other models. They do not require a tricky to use "membrane" to connect ITO, on-glass, traces of the screen to your PCB's traces. and they do not require expensive or hard to find connectors. They feature a 12 pin 0.6mm pitch solderable tab. Ohh and they have a built in Whiteish blue LED backlight.
Here are some I bought from the link above (Note I'm not associated with the ebay seller) at the time of writing the cost ~$2.80 ea [attachment=1]
The controller is the STE2007 ( link ). The display is interfaced with a 9 bit serial interface, 8 data bits and a Data/Command bit. The display area is 96x68 pixels.
Here is a demo of what the display looks like when on, controlled by a cheap MSP430 IC. [attachment=0]
I'll be doing some measurements and testing soon, for current consumption etc. I imagine these will be similar to other cheap Nokia LCDs like the 5110's. I would like to make a watch with one of these displays hopefully they are low power enough.
[quote author="phirephly"]This implies an internal resistance of the coin cell on the order of 12-30 ohms.[/quote] That backs up the data in the energizer datasheet for the CR2032. it's stated a typical IR of 10-40 Ohms.
[quote author="phirephly"] Considering it's multiplexed, I also hypothesize that you may have gotten away without the FETs. [/quote] I possibly may have gotten away without then on a fresh Battery. But I think the FETs help out more when the battery runs down a bit.
[quote author="phirephly"] Of course, if I hadn't missed your last post, I may not have bothered...[/quote] It's always good to experiment. A fun and informative way to spend time :)
Of course I could use a Li-ion 2032. they have much higher discharge rates than standard CR2032 cells. And they run at 3.6v and are rechargeable. But I'm scared of shorting them out with the cheap battery holsters I have, so I haven't bought any. :/
[attachment=0] I just got this bad boy from some hongkong ebay seller. It's a 100mW 433Mhz Transceiver based on the CC1101. Exactly the same radio module that is inside the CC430 in my ez430-Chronos watch. My hope is to interface this with TI's wireless stack and create a central node which will sync my Chronos watch automatically.
[quote author="sqkybeaver"]for most of my projects i don't need 10 boards, just one. [/quote] well yea. I've only used 2 so far, and I might solder up a few more eventually. compared to batchPCB which starts out charging you with a $10 fee before you've even bought any PCB space. seeed/itead are fantastic. This problem won't stop me using their service again, I'll just spend more time double checking before I solder up the next board I have fabed.
[quote author="AndThen"]
Quote
So if all 10 of my boards are e-tested how did this happen.
Mmm circuit loop maybe? [/quote] Well my board certainly will not function as intended without these two traces.
[quote author="AndThen"]
Quote
None of my boards have any marks on the edges like some one's I've received from the PCB drawer do.
Seems you were processed before the morning coffee was finished maybe. [/quote] They may have spent to much money on coffee that they couldn't afford a new black marker.
I did solder up one board without the mosfets, using small pieces of solder shorting the Gate and Drain pins. The LEDs aren't as bright when you have an entire row lit up. The ON Semi 74HC595 parts I'm using state 35mA/pin and 75mA total. so the mosfets do help to sink some extra current. I would have used mosfet packs (2+ mosfet's per IC) but these sot23 devices came up the cheapest (~0.09c each).
The display module is bi-coloured so the current consumption would be less. In practice it maxes at around 80mA due to the current sourcing limitations of the high side 595.
From some initial testing when the devices goes to sleep it uses 0.15µA total. Using this figure a standard energizer battery (datasheet) of 240mA/h the device would last for 700 years in sleep, the batteries shelf life would likely be shorter than this figure.
I've ordered from element14 the Australian version a few times. great because they have free courier shipping to Australia from the Australian site. however they charge an average of %20-40 markup on prices compared to digi-key/mouser. Since digi-key charge a flat rate of $30 for all orders <$200 to Australia elemnt14 is cheaper for individual parts.
One interesting thing about element14 Australia is how they package and ship parts. my last order had 19 lines, mostly one off parts. they shipped them in 5 different parcels that arrived over the course of about 2 weeks. A few before Christmas and a few after new years. I thought it might be because they shipped directly from overseas warehouses. But all the origin addresses were from the same place.
Related: I bought one of those 3rd hand tools, the joints ended up rusting up so I had to toss it out. Not sure if it's because mine was cheap or if I'd spilt something on it at some point.
