Digital PMR Radio Processor
CMX7131/CMX7141
6.3 Function Image™ Loading
NOTE:FI loading from serial memory is not supported when FI-3.1 is used in I/Q mode because the serial
memory interface is used for CMX994 control.
The Function Image™ (FI), which defines the operational capabilities of the device, is 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 or programmed into an external serial memory. The maximum possible
size of a Function ImageTM is 46kbytes, although a typical FI will be less than this. Note that the BOOTEN
pins are only read at power-on or following a C-BUS General Reset and must remain stable throughout the
FI loading process. If the CMX994 is to be used, then the BOOTEN pins MUST both be held high once the
FI load has completed, otherwise they are ignored by the CMX7131/CMX7141 until the next power-up or
C-BUS General Reset.
The BOOTEN pins are both fitted with internal low current pull down devices.
For C-BUS load operation, both pins should be pulled high by connecting them to DV
either directly or
DD
via a 220k resistor (see Table 10).
For serial memory load, only BOOTEN1 needs to be pulled high in a similar manner, however, if it is
required to program the serial memory in-situ from the host, either a jumper to DV or a link to a host I/O
DD
pin should be provided to pull BOOTEN2 high when required (see Table 10). The serial memory interface
is shared with the Auxiliary C-BUS port which controls the CMX6x8 Vocoder using a separate chip select
(SSOUT) pin. During boot operations, the SSOUT will be disabled. Once the boot operation has
completed, the serial memory chip select (EPSCSN) will be disabled and the SSOUT will become
operational.
Once the FI has been loaded, the CMX7131/CMX7141 performs these actions:
(1) the product identification code ($7141 or $7131) 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 IDLE mode and becomes ready for use, and the
Programming Flag (bit 0 of the Status register) will be set.
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 must be power cycled before an attempt is made to re-load
the FI and re-activate.
Both the Device Activation Code and the checksum values are available from the CML Technical Portal.
Table 10 BOOTEN Pin States
BOOTEN2
BOOTEN1
C-BUS Host load
reserved
Serial Memory load
No FI load
1
1
0
0
1
0
1
0
Note:
Note:
Following a General reset, reloading of the Function Image is strongly recommended.
For operation with the CMX994, BOOTEN1 and BOOTEN2 MUST be held high at all times.
2014 CML Microsystems Plc
Page 32
D/7141_FI-3.x/6
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