Marine AIS SART Processor
CMX7045
7.3 Function Image™ Load and Activation
The Function Image™ (FI) file, which defines the operational capabilities of the device, may be obtained
from the CML Technical Portal, following registration. This is in the form of a 'C' header file which can be
included into the host controller software. The Function ImageTM data file is no more than 24kbytes.
Once the FI has been loaded, the CMX7045 performs these actions:
(1) The product identification code ($7045) is reported in C-BUS register $C5
(2) The FI version code is reported in C-BUS register $C9
(3) The two 32-bit FI checksums are reported in C-BUS register pairs $A9, $AA and $B8,
$B9
(4) The device waits for the host to load the 32-bit Device Activation Code to C-BUS register
$C8
(5) Once activated, the device initialises fully, enters Deep Sleep mode and becomes ready
for use. The Activation Register Ready (ACT) flag (bit 0 of the Status register) will be set
(6) Once the Deep Sleep bit (Status2 b:13) has been set, the host may then power down the
Analogue sections of the device to minimise power consumption (typically while the host
is waiting for the external GPS to output a valid position fix)
(7) When the host decides that the device should be returned to active mode in order to
configure the device or transmit an AIS burst, it should first power-up the Analogue
sections and then send the “Leave Deep Sleep” command.
The checksums should be verified against the published values to ensure that the FI has loaded correctly.
Once the FI has been activated, the checksum, product identification and version code registers are
cleared and these values are no longer available. If an invalid Activation code is loaded, the device will
report the value $DEAD in register $A9 and become unresponsive to all further host commands (including
General Reset). A power-on reset is required to recover from this state.
Both the Device Activation Code and the checksum values are available from the CML Technical Portal.
Following a General Reset, reloading of the FI is required.
7.3.1 FI Loading from Host Controller
The FI is downloaded into the CMX7045 at power-up over the C-BUS interface. Wait for the ACT flag to
be set (Status register $C6 bit 0), then the data can then be sent directly over the C-BUS to the
CMX7045.
Each time the device is powered up or reset, its FI must first be loaded and then activated. These two
steps assign internal device resources and determine all device features. The device does not operate
until the FI is loaded and activated.
The download time is limited by the clock frequency of the C-BUS, with a 5MHz SCLK, it should take less
than 500ms to complete.
2013 CML Microsystems Plc
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D/7045FI-1.x/4
CMLMICRO [ CML MICROCIRCUITS ]
