Published July 22nd, 2007
in Techical Stuff! and COMMZGATE Products.
If you are programming an application to interface with an GSM modem hardware device to send and receive SMS Text Messages, you will most likely be communicating with the GSM modem device using AT Commands.
When issuing commands to the GSM modem device, you will get back a series of return codes from the device, which is in turn a result of how the GSM modem device had interacted with the GSM network.
The return codes are in the form of 1 to 3 digit numbers.
Here is the full list of the possible return codes and what they mean:
CMS Error code list for GSM Modem devices
1 - “Unassigned (unallocated) number”
This cause indicates that the destination requested by the Mobile Station cannot be reached because, although the number is in a valid format, it is not currently assigned (allocated).
8 - “Operator determined barring”
This cause indicates that the MS has tried to send a mobile originating short message when the MS’s network operator or service provider has forbidden such transactions.
10 - “Call barred”
This cause indicates that the outgoing call barred service applies to the short message service for the called destination.
Continue reading ‘CMS Error Codes when working with GSM Modems’
Published July 16th, 2007
in Techical Stuff!.
When sending SMS in English text, the message is actually encoded with a character set that ain’t quite the full set that you see on your computer keyboard.
As SMS messages can only carry 140 bytes worth of data, a new Alphabet was invented that will only take up 7-bits per character so that more characters can be squeezed into this 140 bytes, resulting in the current 160 character limit for SMS Text Messaging.
(Most mobile handsets will be able to decipher message transmitted in either 7-bit or 8-bit encoding, but the message transmitted in 8 bit encoding will obviously have a smaller character limit )
This new 7-bit Alphabet ( GSM 03.38) is the default character set that most SMSCs and SMS gateways support. This 7-bit Alphabet also means that there are some characters you should avoid or prevent from sending when designing your SMS sending applications.
The GSM 03.38 7-bit Alphabet set is shown as follows, along with the character’s hexadecimal equivalent representation:
| |
x0 |
x1 |
x2 |
x3 |
x4 |
x5 |
x6 |
x7 |
x8 |
x9 |
xA |
xB |
xC |
xD |
xE |
xF |
| 0x |
@ |
£ |
$ |
¥ |
è |
é |
ù |
ì |
ò |
ç |
LF |
Ø |
ø |
CR |
Å |
å |
| 1x |
Δ |
_ |
Φ |
Γ |
Λ |
Ω |
Π |
Ψ |
Σ |
Θ |
Ξ |
ESC |
Æ |
æ |
ß |
É |
| 2x |
SP |
! |
“ |
# |
¤ |
% |
& |
‘ |
( |
) |
* |
+ |
, |
- |
. |
/ |
| 3x |
0 |
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
: |
; |
< |
= |
> |
? |
| 4x |
¡ |
A |
B |
C |
D |
E |
F |
G |
H |
I |
J |
K |
L |
M |
N |
O |
| 5x |
P |
Q |
R |
S |
T |
U |
V |
W |
X |
Y |
Z |
Ä |
Ö |
Ñ |
Ü |
§ |
| 6x |
¿ |
a |
b |
c |
d |
e |
f |
g |
h |
i |
j |
k |
l |
m |
n |
o |
| 7x |
p |
q |
r |
s |
t |
u |
v |
w |
x |
y |
z |
ä |
ö |
ñ |
ü |
à |
The Letters A to Z and numbers 1 to 10 (plus the symbols in between) corresponds to the ACSII encoding table.
Make sure your browser has UTF-8 encoding turned on to read the table above!
Published June 20th, 2007
in Techical Stuff! and COMMZGATE Products.
WAP PUSH enables the delivery of multimedia content to mobile devices without the need for the full-fledged MMS delivery protocol. Instead, a hyperlink is delivered to the mobile device of the recipient as a Service Indication message. The recipient mobile device will automatically prompt the recipient to download the content on the hyperlink and display it over a GPRS/WAP connection.
Formatting a proper WAP PUSH message as hexadecimal string has been something of a mystery to many people, as there is close to no useful documentation on the Web on this, and Nokia’s own documentation is very cryptic at best.
Hopefully, the following provides a clear and easy-to-understand guide on how to construct WAP PUSH messages!
Basics: ASCII to Hex Conversion
A WAP Push message essentially consists of the Internet URL containing your multimedia content, and this URL is wrapped by some SMS-specific headers, which we will explain below
Your need to first convert your URL into a hexadecimal string. Use the table found at the following webpage to convert each character in your URL string into its hexadecimal equivalent:
http://www.prepressure.com/library/binhex.htm
Continue reading ‘How to format a WAP Push Message as a Hexadecimal String’
Published June 11th, 2007
in Techical Stuff! and COMMZGATE Products.
ING Private Bank has enhanced their in-house COMMZGATE Setup to a pretty heavy-duty one involving multiple GSM modems and the ever-amazing N-Port IP-based Serial Port Appliance server.
The N-Port application is basically a specialized server appliance with its own IP address and up to 16 RS-232 serial ports extending out of the back of it for connection with serial devices such as GSM modems.
The COMMZGATE Enterprise Server installed on-site communicates with the N-Port using the supplied management program (runs on Windows and Linux).
The enhanced setup allows for increased message throughput as well as sophisticated message routing based on destination mobile number country codes.
Wikipedia has published a comprehensive entry on SMS Gateways. Check it out
HERE.
Many of the email-to-SMS capabilities offered by the Mobile Operators listed in the article is not readily available in this region. For a local alternative, check out the Email-to-SMS solution offered by COMMZGATE.
Continue reading ‘Wikipedia Entry about SMS Gateways’
