3

MC2 Chip

DRAM Parity Error Interrupt Control Register

The DRAM Parity Error Interrupt Control Register controls the interrupt logic for parity error interrupts. In the MVME172, the parity control and interrupt logic is contained in the DRAM Parity Error Interrupt Control Register and the DRAM Control Register located at $FFF4201C and $FFF42048 respectively.

ADR/SIZ

 

 

 

 

 

$FFF4201C (8 bits)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

BIT

31

 

30

 

29

 

28

27

 

26

25

 

24

 

 

 

 

 

 

 

 

 

 

 

 

 

 

NAME

 

 

 

 

INT

 

IEN

ICLR

 

IL2

IL1

 

IL0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

OPER

R

 

R

 

R

 

R/W

C

 

R/W

R/W

 

R/W

 

 

 

 

 

 

 

 

 

 

 

 

 

 

RESET

0

 

0

 

0 PL

 

0 PL

0 PL

 

0 PL

0 PL

 

0 PL

 

 

 

 

 

 

 

 

 

 

 

IL2-IL0

These three bits select the interrupt level for the DRAM

 

 

 

 

parity error detection. Level 0 does not generate an

 

 

 

 

interrupt.

 

 

 

 

 

 

 

 

 

ICLR

 

Writing a logic 1 to this bit clears the DRAM parity error

 

 

 

 

detection interrupt. This clears the INT bit in this register.

 

 

 

 

This bit is always read as zero.

 

 

 

 

 

IEN

 

This bit set to a one enables the parity error interrupt. If

 

 

 

 

this bit is set to a one, and the PAREN and PARINT bits

 

 

 

 

are set to 01 or 11, and a parity error occurs, an interrupt

 

 

 

 

is generated at the level programmed in the IL2-IL0 bits.

 

 

 

 

The PAREN and PARINT bits are located at $FFF42048

 

 

 

 

at bit 26 and 25.

 

 

 

 

 

 

 

INT

 

When this bit is high, a interrupt is being generated due to

 

 

 

 

a DRAM parity error. The interrupt is at the level

 

 

 

 

 

programmed in IL2-IL0.

 

 

 

 

3-22

Computer Group Literature Center Web Site

Page 210
Image 210
Motorola MVME172 manual Dram Parity Error Interrupt Control Register, IL2-IL0, Iclr, Ien