Gemalto Cinterion, Hardware Interface Description, Page: 68 / 70

Cinterion
®
Java Terminals Hardware Interface Description
8.4 Configuration via I
2
C Interface
69

EHSxT_BGS5T_HID_v02 2014-05-23
Confidential / Preliminary
Page 68 of 70
Examples
The following two samples show how the watchdog can be configured via the I
2
C interface, us-
ing the AT^SSPI command (at RS-232/ASC0) to transfer the I
2
C user data. Please refer to [1]
for more information on the AT command AT^SSPI and on how to configure and control the
data transfer over the I
2
C interface.
The above Table 25 specifies the address register that can be used in I
2
C configuration com-
mands.
The first example sets GPIO12 to “output“. It therefore configures a write register marked as
“W“ in Table 25 .
Figure 18: Write data to address register
AT^SSPI=
CONNECT
<aD41401>
{a+}
<bD50001>
{b+00}
#
OK
Open the Java Terminals I
2
C data connection.
Indicates that the connection is open.
WRITE command enclosed by <>: “a“ is a command ID to better identify and match
acknowledgments, “D4“ indicates the slave address (write mode), “14“ specifies
the address register GPIO12, and “01“ sets the data byte (i.e., line is “output“).
Note : The data byte value is only written if valid, i.e., if in the specified range. After
a WRITE command, the status code of the operation is saved to the status register
(SR) and a subsequent READ command from the status register will then return
the latest status code as listed in
Table 26 .
Acknowledgement enclosed in curly brackets of a successful data transmission.
READ command enclosed by <>: “b“ is a command ID to better identify and match
acknowledgements, “D5“ indicates the slave address (read mode), “00“ specifies
the address register SR, and “01“ sets the data length to be read.
Note: The READ
command can only be called in conjunction with the SR address “00“ and the data
length of one byte “01“.
Acknowledgement enclosed in curly brackets of a successful data transmission,
together with the response code “00“ indicating that the command was successful-
ly executed.
Close data connection.
Connection closed.
PC Watchdog
Write: Set GPIO12 to “output“
GPIO12:
01
SR:
00
Read from status register (SR)
Command
executed
successfully