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IEC 62056-21, implement the protocol over a gsm connection

The protocol IEC 62056:21 tells us how to deal with enegy meters, it's quite easy!
The part where I am stuck is the implementation over a GSM data channel. Normally I would set things like:
300 baudrate
1 parity bit (even)
But the meter is not connected via serial connection but, instead, it has a sim. Using a modem I can call the meter using:
AT&C1
ATDNumber
Problem 1: Settings
The modem calls the meter with different settings (baudrates, stopbits, parity) compared to the protocol ones, e.g.
9600 baudrate for call
300 baudrate for first messages
xxxxx new baudrate shared between master and slave
Can I change these parameters during call?
Problem 2: Send data
After I establish a call, I would send to the meter things like:
/ ? Device address ! CR LF
Here's the missing piece, I don't know how to send this data over the call
I am reading and trying several libraries (like J62056, pyserial), but I've found nothing about sending data via gsm call
EDIT
I read a trace of a proprietary software, and I got this:
TX: 140ms AT&C1E0V0
RX: 32ms 0
TX: 1203ms
ATDT ##########
RX: 34656ms 1
RX: 0ms 5
RX: 0ms
TX: 3234ms <NUL><NUL><NUL><NUL><NUL><NUL><NUL><NUL> *what is this?*
TX: 594ms /?########! (this the Request message) **start sending data**
The < NUL > part is not Clear, and this is where the modem starts to send data
Edit:
I read about the 8 null chars, they're just a check-in sequence.
At the moment, after the modem established the call I translate my 8 bit no parity sequence into a 7 + parity one. Now i am able to send and receive data from the meter, I must test other feature before writing my solution to this answer

Without knowing anything about IEC 62056:21, if your energy meter supports this over GSM circuit switched data (CSD), nothing it says about speed and parity in the normal non-GSM case is relevant at all.
Because the data call you set up will be non-transparent CSD (NTCSD). A transparent call would have treated the gsm connection as much as just an electrical wire as possible (which in best case is difficult1), forwarding each byte received immediately and with no buffering nor with any retransmission support. A non-transparent connection on the other hand will receive/send its data to an intermediate entity which in turn communicates with the other end point, and will support buffering and retransmission.
For GSM NTCSD, the part of the phone responsible for data handling is called TAE (Terminal Adapter Equipment) or TAF (T. A. function), and the relevant protocol2 is called RLP (Radio Link Protocol) which is specified by 3GPP in specification 24.022. It is a link-layer protocol similar to HDLC, and it communicates with a unit in the GSM network called MSC (Message Switching Centre). It is then then MSC which communicates with the other end, on a different and completely separate communication line (which can be PSTN, ISDN or mobile network depending on what kind of device the remote end is).
mobile modem <----link1----> MSC <----link2----> remote endpoint
The important thing here is that the two links are 100% independent, and they do not have to be the same speed.
Thus whatever speed your energy meter is using over some serial interface between itself and the embedded modem with SIM card is independent of the radio link1 speed which itself is independent of the network link2 speed which your modem will have.
So the above should be an answer to your question, but let me fill in some more information with regards to the speeds of link1 and link2, because this can be controlled with two AT commands AT+CBST and AT+CHSN (specified in 27.007).
The basic GSM data traffic channel is called TCH/9.6 (Traffic Channel), which is a channel with net 9600bit/s speed (seen by the user) and 12000bit/s gross speed (seen by the network). In order to enhance throughput
HSCSD (High Speed CSD) was developed which introduced a new channel coding and a new channel TCH/14.4 which had 14500bit/s gross speed and 13200bit/s net speed (which of course all the marketing people presented as 14.4 speed even though that not was really true).
In addition HSCSD allowed for bundling multiple timeslots together (multislot). A frequency band in GSM is divided into 8 timeslots, where an active call occupies one timeslot in the downlink direction and one timeslot in the uplink direction. Thus a cell tower configured to support only one frequency band supports maximum 8 simultaneous calls.
What HSCSD introduced was the possibility to set up a call that could use multiple (adjacent) timeslots, for instance two downlink timeslots and one uplink (denoted 2+1). The different multislot configurations a phone or network supported were categorised in multislot classes3 (with 2+1 being multislot class 10 as far as I remember).
Since HSCSD both was an added value and occupied more network resources this was something that was billed higher than a normal 1+1 9600 call, and thus the users had to have some control over if they used HSCSD or not. This was
done by introducing the AT+CHSN command which controls the link1 speed.
Support for hinting to the MSC what speed it should use for link2 was implemented by the AT+CBST command (which already existed before HSCSD).
Since the AT command is terminated in the mobile phone, its value had to be forwarded to the MSC in some way, and this was done out-of-band (with regards to the RLP data link) in a Bearer Capability Information Element in some of the call setup messages.
So, that's probably more than you need to know about speeds in a GSM network for a NTCSD call, but having developed and maintained the NTCSD call stack in Ericsson's mobile phones for over a decade, this is something I know quite well...
1
While there are standardized some support for transparent data, this was more of a legacy thing done in the 90-s in order to support equipment made in the 80-s. Operators do not want to have this supported today because it is a pain in the butt to get working and to support.
Fax over GSM for instance was such a transparent bearer, and it was a massive test everywhere approach with no guarantee that it would work even if you followed the specification fully. You had to do your best effort implementation and then you had to travel all over the world testing it and try to fix all the issues that would pop up (which they absolutely did. And even if the problem was something wrong with the network, the operator might not want to fix it so you had to add some custom workaround).
One of the guys working with fax support told me that in some cases they had to start sending the response before they had gotten the request in order for the timing to work out (e.g. they had to guess and anticipate what the remote fax would do).
It is not without a reason that phones manufactured and operators today do not support fax like they did in the 90-s, early 2000.
2
In addition there is L2RCOP which is just a framing adoption between packet based RLP and the physical serial interface.
3
CSD and GPRS both supported multislot, but not necessarily the same class, i.e. CSD multislot class is independent from GPRS multislot class.

Possible to modify mini controller/micro controller code on store product?

My girlfriend recently bought a product for her skin, its basically a mask with lights on the inside that runs a power cord similar to an auxiliary cord into an auxiliary port on a mini controller. It is only good for 30 uses, every time you turn it on, an lcd screen counts down til it hits 0, then you have to buy a new controller.
I find it extremely wasteful to buy a new plastic controller after 30 uses. My question is it possible to somehow connect this device to my laptop through the aux port or aux port extension and modify the code written on it.
I work as a web developer by trade, so I am no stranger to code. I just need to know how to connect it, read the code and compile the code, etc, to modify the counter or remove it.
It is ЯU 94v-0 mini controller (Yes, the R is backwards)
Interestingly enough if I plug the mask into my iPhone or Mac, it will power one set of lights (there are two types/sets), but not the other.
Thanks in advance for the hackery advice.

I Have Better IDEA! Just buy new device (This device has an memory ATMLH436, which is basically same as AT24C02 eeprom chip), disconnect the WP pin and connect it only with the VCC pin, it then can't write the counter down (since it will be write protected), every time you pull the batteries out and in again, it will be as fresh as new. Should work like a charm :D
Here is the historical answer, maybe usefull to someone in the future:
How to hack instruction.
This device has an memory ATMLH436, which is basically same as AT24C02 eeprom chip, which is an EPROM with I2C interface, it is 2 KBytes memory. And the counter is most likely stored on this element.
You need to buy a new device, connect the not used eeprom to a i2c programator (you need to buy one, or ask a friend, I remeber this as a simple device connected to a rs232 port, but you can find one for usb), read the memory content and store it in a file and then you can use this file to reprogram the eprom to the original "new" state every time you want.
How to connect the i2c eeprom to mac:
hmmm, you need to have an i2c programator, that's first step.
Check the one you're about to buy if it has a Macintosh compatible software for reading/ writing.
If not, maybe use other computer.
remeber that in order to be able to program the device you need to connect the pin 7 (Write protect pin) to the ground. Here's the chip spec: http://www.atmel.com/Images/doc0180.pdf
Basically in oreder to communicate with the device you need:
know the address of the device - it is set by the A0,A1,and A2 pins connected either to ground or VCC - the programator soft will require that address.
connect the SDA, SCL and GND pins to the programator.
the chip need power supply of 5V connected beetween GND (-) and VCC (+) to operate.
In order to program the WP pin needs to be connected to GND.
There are big chances that: A0,A1,A2 and WP are grounded, but I can't be sure.
In case of this scenario the address of the device is 1010000 and there's nothing left that needs to be done in oreder to program it. I assume if the WP pin is not grounded you can disconnect it from whatever it is connected to and hardwire it to ground - should not affect normal operation of the device. probably you don't need to unsolder the chip in order to be able to read/write it, you need to connect GND, SDA, SCL and VCC. I would make a connector for these 4 pins to have it accessible from ouside of the device.
In order to make my life easier for many reprogram cycles, I would solder some connector to not have to disssassemble the device each time I need to reprogram it.
There are small chances that the counter is in the fat black round dot on the PCB, in which case there's nothing you can do to reset it since it is some custom chip without spec - if you have a great lab with X-RAY machine (like https://www.hawkerrichardson.com.au/electronic-production-systems/inspection-test-a-repair/unicomp-ax-8200) and other such stuff + lot of experience you could :) but rather not many people have such toys since they are very expensive :)
There are some pins to connect to the rounded chip, but I don't have any idea how to use them, what's the protocol or anything...
but if they could produce eprom inside of it, they wouldn't probably use any additional external eeprom because of the costs. But since eeprom production is not so easy as the regular chip, they use rather external memory from other supplier rather that producing one by themself - it's one logical argument that the counter is there in the AT24C02.

The correct way to hack this thing would be to listen to the I2C communication line with a scope. Note the exact binary sequence.
Then remove the external eeprom entirely and replace it with another MCU, which only has one task and that is to reply as the main MCU expects it to do. Though of course it never saves the down-counter.
Essentially you'd get this sequence each time you power up:
Main MCU: "Hello my eeprom, can I get the counter?"
Hack MCU: "Err yes I am totally an eeprom, the counter is 5."
Main MCU: "Store the counter value 6".
Hack MCU: "Roger that" (does nothing).
You'll get the same sequence over and over.
To succeed you need to know: microcontroller programming, I2C, basic electronics, soldering.

How to capture an Infrared signal pattern & frequency for later use?

I'm wanting to create an Android app that will send IR signals, but I don't know how to find the signal patterns or the frequencies from the original transmitter.
I purchased a small USB IR receiver (not Microsoft, but uses the Microsoft EHome drivers) and I can see the patterns from WinLIRC, but they are barely consistent, and trying to use any of them doesn't work on the receiver. I also am not sure what frequency to transmit on. I have my app sending back the signals and I can see them in LIRC, and they're accurate, but the receiver from the original remote doesn't respond to it.
How can I get the info from the original transmitter, accurately, without spending tons of money on something like an oscilloscope?

Receive and read GATT notifications on Android

So right now, I'm currently using the TI SensorTag and edited it such that it will send a GATT notification with some data every time I press one of the switches on the device and followed this code where moisture is the data I'm trying to send.
static void sendData(void )
{
int length=0;
while(moisture[length] != NULL)
{
length++;
}
attHandleValueNoti_t nData;
nData.len = length;
nData.handle = length;
osal_memcpy( &nData.value, &moisture, length );
// Send the Notification
GATT_Notification( 0, &nData, FALSE );
}
Now on the Java side, TI provided the SensorTag app source code so I'm editing that to receive the data and save it into a .txt file for later retrieval. I was able to get the app to create a new directory on startup if it does not exist and create the .txt file and populate it with random strings with the same button press as the one used to send the data. A quick question I had about this is should this be done or should I use separate buttons?
What I'm having a huge issue even understanding is how to read the incoming notification or data. From what I understand so far, you need to know the characteristic or something of the incoming notification to read it? I do have notifications enabled on my central device so I know that I have at least that covered. For this kind of data transfer, I don't need to use any UUID things, correct? And if I do, would I be able to piggyback on one of the existing sensor services to do so? Or perhaps use the test service?
I've read a decent amount on BLE communications but I just can't seem to get it. How do I read the incoming notification or data I sent from the SensorTag through BLE?

A quick question I had about this is should this be done or should I
use separate buttons?
It's totally your call. If I were you, I would stick on to one button since BLE devices are better if designed the most simplest way. KISS.
From what I understand so far, you need to know the characteristic or something of the incoming notification to read it?
Yes, you need the same profile running on both the peripheral and the central to enable notifications. In Bluez for example, run the bluetoothd daemon with all experimental profiles to communicate with a TI Sensor tag like this: bluetoothd -E . The same logic applies for a central running on Java. Reference: http://www.amazon.com/Inside-Bluetooth-Communications-Sensing-Library/dp/1608075796
For this kind of data transfer, I don't need to use any UUID things, correct?
No, you don't have to since you aren't creating a new service but rather using the moisture sensor service already available on the device.
I've read a decent amount on BLE communications but I just can't seem to get it.
To know more about Bluetooth terminology such as profiles, services, characteristics, asymmetric architecture, etc, please read the following references to understand the theory behind what's taking place:
http://www.amazon.com/Inside-Bluetooth-Communications-Sensing-Library/dp/1608075796 (use this if you are already into the technical details of the project)
http://www.amazon.com/Bluetooth-Low-Energy-Developers-Handbook/dp/013288836X/ref=pd_sim_14_1?ie=UTF8&refRID=13KZ3RZ0VW93CK91RCM3 (this gives a more general picture of the BLE)

How to handle multiple video streams in Red5?

I am writing a Red5 application that provides 1-on-1 video chat to a Flash client over RTMP.
Unfortunately most tutorials I was able to find were sketchy at best and the documentation of Red5 itself tends to be vague when it comes to API concepts and intended usage.
In short, I am a bit stuck and looking for hints on Red5 ApplicationAdapter implementation. Gnarly details are as follows:
First of all, the connections come in two flavors: visitors and consultants. A visitor should be able to indicate which consultant it wishes to communicate with. A consultant simply gets connected to the requesting visitor as long as the consultant is not busy servicing another.
Obviously, every RTMP connection has two-way traffic: both sending and receiving video. From the standpoint of the server, connections bring in a bunch of video streams that get their receiving endpoints assigned by request.
Since several video conversations can be in progress simultaneously, the main task of the application is to handle the mapping of visitor streams to consultants and provide a list indicating each consultant's state (busy/available) via AMF.
So, all in all, I have a pretty good idea what I am aiming for but how to achieve it with Red5 is still a bit of a mystery.
Hopefully someone can enlighten me in any or all of the following:
What is the easiest way to establish the connection type (visitor/consultant)?
Which API classes should be used to implement a persistent, globally accessible list of active connections for reporting the state of each consultant?
How to switch receving endpoints dynamically when the goal is to connect a specific visitor to the selected consultant?

Saul ,
1.What is the easiest way to establish
the connection type
(visitor/consultant)?
assuming that both(visitor/consultant) are using flex client via which they start publishing their live video stream ,here you need to make sure that each published video stream name is unique (HOWTO is already mentioned in demo apps)
2.Which API classes should be used to
implement a persistent, globally
accessible list of active connections
for reporting the state of each
consultant?
and for providing the list of active connections you simply need to store(preferably in your db) each user's id with the stream name (which is also available as a tutorial demo app) to connect to.
I believe all the code is available for the red5 demos Do try oflaDemo , simpleSubscriber , fitcDemo demo apps.
I hope I am closer to your solution.

Since Oflademo or red5 is capable of 1v1 chats, then replicate this code to make around 50 chats. You can maintain a table with the following columns :
chat room number (1 to 50)
user1
user2
status(0 or 1 - unoccupied or occupied)
If let say a visitor V22 wants to get consulted from consultor C33, then a program can detect the first unoccupied room from 1 to 50, if the 7th room is unoccupied then, redirect V22 and C33 to room 7 and change status to 1(occupied). After the video call, the status can be reset to 0, and the table at roomno:7 , user1 of roomno:7, user2 of roomno:7, can be set to NULL. Its like maintaining tables in a restaurant in a computer.
You can basically develop multiple chatting using 1to1 using a database and php queries, no need to edit any swf code or maintain a complicated server etc.