3

MC2 Chip

LANC Error Status Register

ADR/SIZ

 

 

 

$FFF42028

(8 bits)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

BIT

31

30

29

 

28

 

27

 

26

25

24

 

 

 

 

 

 

 

 

 

 

 

NAME

 

 

 

 

 

PRTY

 

EXT

LTO

SCLR

 

 

 

 

 

 

 

 

 

 

 

 

OPER

R

R

R

 

R

 

R

 

R

R

C

 

 

 

 

 

 

 

 

 

 

 

 

RESET

0

0

0

 

0

 

0 PL

 

0 PL

0 PL

0 PL

 

 

 

 

 

 

 

 

 

 

 

 

SCLR Writing a 1 to this bit clears bits LTO, EXT, and PRTY.

Reading this bit always yields 0.

LTO, EXT, PRTY

These bits indicate the status of the last local bus error condition encountered by the LANC while performing DMA accesses to the local bus. A local bus error condition is flagged by the assertion of TEA*. When the LANC receives TEA* if the source of the error is local time-out, then LTO is set and EXT and PRTY are cleared. If the source of the TEA* is due to an error in going to the VMEbus, then EXT is set and the other two status bits are cleared. If the source of the error is DRAM parity check error, then PRTY is set and the other two status bits are cleared. If the source of the error is none of the above conditions, then all three bits are cleared. Writing a 1 to bit 24 (SCLR) also clears all three bits.

3-30

Computer Group Literature Center Web Site

Page 218
Image 218
Motorola MVME172 manual Lanc Error Status Register, LTO, EXT, Prty