Guardian G25AMK005, Technical Manual

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3-18 G U A R D I A N V H F 1 1 0 W M O B I L E
3.6.2.3.2 Full Start-Up Software
If a valid H8 program image exists, the full start-up code executes. This involves initializing RAM, DSP, keypad,
user interface, FPGA, transceiver, etc., executing the start-up BIT, and transferring control to the main scheduler.
3.6.2.3.3 FPGA Configure Software
At start-up H8 configures the FPGA using data from the main Flash memory and transferring it via a synchronous
serial bus to the FPGA.
3.6.2.4 Shut Down Software
At normal shut down when the front panel on/off switch is off, the H8 software executes a clean shut down to the
transceiver, DSP, and user interface (UI), saves any usage data to the Flash, and releases the main power supply. In
cases where the power is removed, the low-power interrupt executes a minimum fast shut down, saving RAM data
as required, with no Flash update.
3.6.2.5 Debug Driver Software
The H8 controller includes software to implement an asynchronous serial port on two input/output (I/O) pins of H8.
Facilities provided include the ability to monitor particular radio variables, and to control specific variables. This
port allows PC serial access to the board during board-level factory testing, through the test connector.
3.6.3 Radio Store
All functional areas of the controller software, including the user interface, access the radio data store, fill control,
and radio software.
3.6.3.1 Physical Data Storage
The radio data is physically stored in 4 devices, all devices are accessible by the controller software.
3.6.3.1.1 H8 Internal RAM
The H8 controller has 2K x 8 of internal RAM. This data is not retained when the radio is switched off or the power
is removed. It is used for short-term storage of frequently accessed variables, stack workspace, etc. to minimize bus
activity when the H8 controller is running. The internal RAM is used as program space from which to execute
during some Flash update operations.
3.6.3.1.2 External RAM
H8 is provided with an external 128k x 8 bit RAM that is backed up for at least 30 seconds when the radio power is
removed, and at all times when a external power is applied with the radio switched off. This device is used as a
variable data expansion area, and stores specific user-entered data that must be retained over power interruptions
(unlock password, etc.).
3.6.3.1.3 Flash ROM
H8 has a 512k x 16-bit Flash read-only memory (ROM) used primarily for program storage. Data in the Flash is
retained permanently. Different areas of the Flash have different characteristics. The boot sector is a 16k block
used for the reprogramming software and the radio serial number. The data in this sector is programmed or block-
erased only in the factory.
The Flash has 15-64k and 6-8k program blocks that can be block-erased and programmed by the boot block code
during normal reprogramming operations, without special equipment and without opening the radio. These blocks
are used for H8 and DSP operating software, radio fill data, and FPGA programming data. The Flash has two small
8k parameter blocks used for changing data that must be stored indefinitely, such as user specific settings and usage
data.