Emerson MVME6100 Series, Installation And Use Manual

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Functional Description
MVME6100 Single Board Computer Installation and Use (6806800D58E )
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4.6.8 Watchdog Timer
The MV64360 internal watchdog timer is a 32-bit count-down counter that can be used to
generate a non-maskable interrupt or reset the system in the event of unpredictable software
behavior. After the watchdog timer is enabled, it becomes a free running counter that must be
serviced periodically to keep it from expiring. Refer to the
MV64360 Data Sheet , listed in
Appendix C, Related Documentation , for additional information and programming details.
4.6.9 I
2
O Message Unit
I
2
O compliant messaging for the MVME6100 board is provided by an I
2
O messaging unit
integrated into the MV64360 system controller. The MV64360 messaging unit includes
hardware hooks for message transfers between PCI devices and the CPU. This includes all of
the registers required for implementing the I
2
O messaging, as defined in the Intelligent I/O
(I
2
O) Standard specification. For additional details regarding the I
2
O messaging unit, refer to
the MV64360 Data Sheet , listed in Appendix C, Related Documentation .
4.6.10 Four Channel Independent DMA Controller
The MV64360 incorporates four independent direct memory access (IDMA) engines. Each
IDMA engine has the capability to transfer data between any two interfaces. Refer to the
MV64360 Data Sheet , listed in Appendix C, Related Documentation , for additional information
and programming details.
4.6.11 I
2
C Serial Interface and Devices
A two-wire serial interface for the MVME6100 board is provided by a master/slave capable I
2
C
serial controller integrated into the MV64360 device. The I
2
C serial controller provides two
basic functions. The first function is to optionally provide MV64360 register initialization
following a reset. The MV64360 can be configured (by switch setting) to automatically read
data out of a serial EEPROM following a reset and initialize any number of internal registers. In
the second function, the controller is used by the system software to read the contents of the
VPD EEPROM contained on the MVME6100 board, along with the SPD EEPROMs for on-board
memory to further initialize the memory controller and other interfaces.