Eurotech PXA320, Руководство пользователя

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System Specification
110120-1000A
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General
This section provides general specifications for the GCM.
Crystal Frequencies
Agencies certifying the GCM for compliance for radio-frequency emissions typically need
to know the frequencies of on-board oscillators. The following table lists the frequencies
of all crystals on the GCM.
Crystals Device Typ. Units
X1 PXA320 core 13.000 MHz
X2 PXA320 RTC 32.768 kHz
X3 USB 2.0 Client (optional) 24.000 MHz
X4 AC ’97 codec 24.576 MHz
X5 Ethernet 25.000 MHz
X6 RTC 32.768 kHz
X7 ADSmartIO 7.3728 MHz
X8 CAN 2.0B bus 16.000 MHz
Real-Time Clock
The GCM includes a Maxim DS1307 serial real-time clock (RTC) chip to retain the
system date and time when the system is powered down. This chip includes non-volatile
RAM that is maintained as long as main or backup power is provided to the chip. A long-
life battery connected to the RTC supplies backup power. For a description of the RTC
function, see Non-volatile Memory , page 13 .
Parameter Typ. Units
Accuracy per month @ 25°C +/-55 sec
Internal non-volatile RAM 56 B
Battery 3 V
Environmental
Parameter Min Typ. Max Units
Commercial operating temperature 0 +70 ° C