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emPC-CXR
(
Hardware Manual
)
•
System Control
©
Janz Tec AG
Rev. V1.2
0x22
EEPROM_CTRL
0x23..0xFF
Reserved
Indicated register settings can be internally saved to EEPROM. These values will then be restored
upon power on of PMON.
Registers that are not documented are reserved for future feature enhancement of the
MCU firmware. They should not be written to avoid compatibility problems with future
versions.
Following you find the description of the defined registers. All voltage related registers are stored in
units of 1/100 V, all time related registers are stored in units of 10 ms (for a maximum parameter of
650s) and all temperature related registers are stored in units of 0.1 degrees Celsius.
Various parameters are visualized in figure 11 and figure 12.
ID
Pointer 0 (16bit, ro)
15
0
PMONID
PMONID
This provides possibility to identify the PMON functionality and will be
used to indicate revisions in the future.
Check for the value 0x0802 to match with this document.
CONTROL
Pointer 1 (16bit, ro)
15
0
EXB
RESET:
Restored from EEPROM
EXB
If this bit is set, the VS input (mid contact on power connector) act as an
power button input. If VS is > 5 V (typ.), the COM Express PWRBTN#
signal is asserted.
If this function is activated, you should program the VS0 threshold to
zero.
Reserved
Reserved bits should be written as zero.
STATUS
Pointer 2 (16bit, ro)
15
14
13
12
11
10
9
8
7
5
4
0
WDR BOR EXR POR
FSTATE
RESET:
undefined
FSTATE
The state of the PMON internal state machine.
POR
Set to one if last PMON MCU reset was a power-on reset.
EXR
Set to one if last PMON MCU reset was an external reset.
BOR
Set to one if last PMON MCU reset was a brown-out reset.
WDR
Set to one if last PMON MCU reset was a watchdog reset.
COMMAND
Pointer 3 (16bit, wo/ro)
15
0
CMDCODE
RESET:
0
CMDCODE
To trigger functions in the PMON firmware, write the corresponding
command code into this register.
