FALCOM JP18 GPS receiver - Hardware manual
FALCOM JP18 GPS receiver - Hardware manual
FALCOM JP18 GPS receiver - Hardware manual
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<strong>JP18</strong> <strong>FALCOM</strong> <strong>GPS</strong> RECEIVER VERSION 1.0.7<br />
5.4 Operational Modes<br />
External configuration inputs permit booting from on-chip boot loader, and<br />
internal flash memory. The default strap configuration for on-chip operational<br />
program ROM is provided by on-chip pullups so that external pull-ups are not<br />
required, saving cost and reducing footprint. Table 1 summarizes the program<br />
memory bootstrap configurations.<br />
DATA 0 DATA 1<br />
ROM Open Open<br />
FLASH Open Connect to GND<br />
BOOTMODE Connect to VIO Open<br />
Table 1: ROM and Flash Operating Mode<br />
Two basic functional modes are of primary concern to the system designer:<br />
ROM and Flash.<br />
● ROM mode. This is the default program memory out of which the <strong>JP18</strong><br />
<strong>receiver</strong> executes its <strong>GPS</strong> application firmware on reset.<br />
No external configuration inputs are required to select<br />
this mode. In this mode, the device is executing firmware<br />
directly from on-chip ROM. The on-chip cache-control<br />
hardware is used to provide a ROM patching facility.<br />
Important: The firmware version ROM is very early<br />
(engineering proof) and was never intended<br />
for production use.<br />
● FLASH mode. This is supported when the DATA 1 line is connected to<br />
GND (ground). On reset, the <strong>JP18</strong> <strong>receiver</strong> executes<br />
firmware directly from the FLASH memory. In this mode,<br />
the device is executing firmware directly from external<br />
non-volatile memory, such as FLASH. This is the<br />
secondary operational mode intended for those<br />
customers who want the flexibility of implementing<br />
software updates. The cache-controller hardware is<br />
used to accelerate read accesses from Flash.<br />
Flash Loader Mode<br />
This is provided to support flash loading. This mode is supported when the<br />
DATA 0 is connected to VIO pin. On reset, the <strong>JP18</strong> <strong>receiver</strong> is set into the<br />
Flash Loader Mode the flash loader program attempts to load the program<br />
to the internal flash via the on-board UART (RXA and TXA) before executing<br />
normal operations.<br />
<strong>GPS</strong> operational modes include: Acquisition, Tracking, and Clock Only.<br />
These modes are accessed and automatically managed through SiRF’s<br />
firmware products:<br />
Acquisition:<br />
RF is on; ARM processor is running; <strong>GPS</strong> DSP core is running highest<br />
duty cycle; RTC is running. This is the highest power consumption<br />
mode of the <strong>JP18</strong> <strong>GPS</strong> <strong>receiver</strong>.<br />
This confidential document is the property of <strong>FALCOM</strong> and may not be copied or circulated without permission.<br />
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