Sending Sms In Pdu Mode - Wave Forms - Motorola D15 Integration And Application Developers Manual

In 8 bit binary is:
01000001 01000010 01000011 01000100 01000101
We truncate off the most significant bit, resulting in a series of seven bit values. The process is to
pack the now unused most significant bit(s) with enough least significant bits from the following
value to fill it up to eight bits.
This results in the string of eight-bit hexadecimal numbers 0x41, 0xE1, 0x90, 0x58, 0x04. By
continuing this process a string of 160 ASCII characters can be stored as a string of 140 bytes
(octets).
The Service Center Address is described in ETSI GSM 04.11.
The Transport Protocol Data Unit is described in ETS GSM 03.40.

4.7.2 Sending SMS in PDU Mode - Wave Forms

4.7.2.1 Sending SMS in RS232 mode
When sending SMS in PDU mode, after executing the at+cmgs=n command, the DCD line goes
active low, and the data is transferred on the TXD line.
After executing the <Ctrl+Z> command, the DCD line goes inactive high again, and the message
is being sent by the phone.
d15 Modem Integration and Application Developers Guide version draft 0.53
'A' 'B'
0x41 0x42
1000001 1000010
01000001 11100001
Figure 34 – Sending SMS in RS232 mode
'C' 'D'
0x43 0x44
1000011 1000100
10010000 01011000
'E'
0x45
1000101
00000100
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