26 IMP2B 3U cPCI Single Board Computer
Publication No. IMP2B-0HH/5
3.13 DMA Engines
The MV64560 provides six independent DMA engines. These can be used to transfer
blocks of data between PCI interfaces, memory and Flash devices without impacting
on CPU performance. Two of these are XOR DMA engines, which may be used for
Memory Initialization, CRC-32 calculation or ECC.
3.14 I
2
C Interface
The following devices are available on the I
2
C interface from the MV64560:
Table
3-8 I
2
C Device Addresses
Device
I
2
C Address Function
LM92
0x90
Board Temperature Sensor
ADT7461
0x98
CPU Temperature Sensor
AT24C64A
0xA0
8 KByte Serial EEPROM
PCF8563
0xA2
Real-Time Clock
DS1682
0xD6
Elapsed Time Indicator
3.14.1
Serial EEPROM
An 8 KByte Serial EEPROM is provided for non-volatile data storage. The device is
write-protected by default, and can be write-enabled by fitting the
EEPROM Write Enable Link (P5 3-4)
and by clearing the appropriate bit in the EPLD
NOTE
Integrity of EEPROM data cannot be guaranteed if a hard reset occurs during an EEPROM write cycle.
3.14.2
Real-Time Clock
A PCF8563 provides real-time clock functions. The device reports year (2 digit),
month, date, hours, minutes and seconds. It has leap year compensation up to 2100
and it also features an alarm capability. Battery back-up is not supported.
For more details see the device data sheet.
LINK
http://www.semiconductors.philips.com/cgi-bin/pldb/pip/PCF8563T/F4.html