Functional Description
MVME197LEIG/D1
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1
DRAM is not disabled by a local peripheral bus reset. Refer to the DCAM and
ECDM chapters in the MVME197LE, MVME197DP, and MVME197SP Single
Board Computers Programmer’s Reference Guide for detailed programming
information.
Battery Backup RAM and Clock
The MK48T08 RAM and clock chip is used on the MVME197LE. This chip
provides a time of day clock, oscillator, crystal, power fail detection, memory
write protection, 8KB of RAM, and a battery in one 28-pin package. The clock
provides seconds, minutes, hours, day, date, month, and year in BCD 24-hour
format. Corrections for 28-, 29-, (leap year) and 30-day months are
automatically made. No interrupts are generated by the clock. The MK48T08
is an 8-bit device; however the interface provided by the PCCchip2 supports
8-, 16-, and 32-bit accesses to the MK48T08. Refer to the PCCchip2 chapter in
the MVME197LE, MVME197DP, and MVME197SP Single Board Computers
Programmer’s Reference Guide and to the MK48T08 data sheet for detailed
programming information.
VMEbus Interface
The local peripheral bus to VMEbus interface, the VMEbus to local peripheral
bus interface, and the local-VMEbus DMA controller functions on the
MVME197LE are provided by the VMEchip2. The VMEchip2 can also provide
the VMEbus system controller functions. Refer to the VMEchip2 chapter in the
MVME197LE, MVME197DP, and MVME197SP Single Board Computers
Programmer’s Reference Guide for detailed programming information.
I/O Interfaces
The MVME197LE provides onboard I/O for many system applications. The
I/O functions include serial ports, a printer port, an Ethernet transceiver
interface, and a SCSI mass storage interface.
Serial Port Interface
The CD2401 serial controller chip (SCC) is used to implement the four serial
ports. The serial ports support the standard baud rates (110 to 38.4K baud).
Serial port 4 also supports synchronous modes of operation.
The four serial ports are different functionally because of the limited number
of pins on the I/O connector. Serial port 1 is a minimum function
asynchronous port. It uses RXD, CTS, TXD, and RTS. Serial ports 2 and 3 are
full function asynchronous ports. They use RXD, CTS, DCD, TXD, RTS, and
DTR. Serial port 4 is a full function asynchronous or synchronous port. It can
Solution Systems Technologies Inc.
720-565-5995 | [email protected] | www.solusys.com
Solution Systems Technologies Inc.
720-565-5995 | [email protected] | www.solusys.com