Phytec phyCORE-OMAP44 Series, Руководство по оборудованию

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Part I: PCM-049/phyCORE-OMAP44xx System on Module phyCORE-OMAP44xx
38 ©
PHYTEC Messtechnik GmbH
2012
L-760e_1
1.4.3.2 Real Time Clock (RTC)
The TWL6030 PMIC, which is populated on the module, provides a real time clock (RTC) with alarm and
time- keeping functions. The RTC is supplied by the backup voltage VBAT if the main power supply VCC_3V3_IN
is not applied.
The RTC stores the time (seconds/minutes/hours) and date (day/month/year/day of the week) information in
binary-coded decimal (BCD) code up to year 2099. It can generate two programmable interrupts. The timer
interrupt is a periodically generated interrupt (1s/1m/1h/1d period), while the alarm interrupt can be
generated a precise time of the day to initiate a wake-up of the platform.
1
1.4.3.3 Power Management
The TWL6030 PMIC provides different power management functions. These include, among others, alternating
between different power groups and in further consequence switching the voltage domains. The peripheral
power request inputs PREQ1. PREQ3 are responsible for switching the different power groups.
Furthermore signals to control the power-on/off state of the system (X_PMIC_PWRON) and to control an
external power supply (X_PMIC_SYSEN) are available.
The following table shows the power management signals and their functions.
Please refer to the Texas Instruments TWL6030 datasheet for further information
1. All special functions of the PMIC such as RTC interrupts, use of power groups, etc. require the PMIC to be programmed via I
2
C inter-
face. At the time of delivery only the generation of the required voltages is implemented . Please refer to the TWL6030 Technical
Ref. Man. for more information on how to program the PMIC.
Pin # Signal name Connected to Description
- PMIC_PREQ1 OMAP44xx (U1) signal
SYS_PWR_REQ Can be triggered by the controller to switch
between power modes.
1
1. All special functions of the PMIC such as use of power groups, etc. require the PMIC to be programmed via I
2
C interface. At the time
of delivery only the generation of the required voltages is implemented . Please refer to the TWL6030 Technical Ref. Man. for more
information on how to program the PMIC.
X1C44 X_PMIC_PREQ2A phyCORE-Connector (X1),
Ethernet controller (U12)
signal PME This signal can be triggered from outside to
switch power group 2. It can also be
triggered in case of a wake-up event of the
Ethernet controller.
1
X1C43 X_PMIC_PREQ3 phyCORE-Connector (X1) This signal can be triggered from outside to
switch power group 3.
1
X1C9 X_PMIC_PWRON phyCORE-Connector (X1) This signal can be triggered from outside to
control system power on/off. A low-level
signal of approx. 2 s initiates a power on,
while a signal longer than 10 s causes a
hardware switch-off.
X1C42 X_PMIC_SYSEN phyCORE-Connector (X1) This output is controlled by the power-
management module and is activated during
power-on/off sequence. SYSEN can be used
to control an external power supply.
Table 7: Power Management Signals