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Programming Issues

DMAC Offboard Error

Description:

Error encountered while the Local Bus side of the DMAC

 

was attempting to go to the VMEbus.

MPU Notification:

DMAC interrupt (when enabled)

Status:

The DLOB bit is set in the DMAC Status register (address

 

$FFF40048 bit 4).

Comments:

This is normally caused by a programming error. The

 

Local Bus address of the DMAC should not be

 

programmed with a Local Bus address that maps to the

 

VMEbus. If the TBL bit is set (address $FFF40048 bit 2),

 

the error occurred during a command table access;

 

otherwise the error occurred during a data access.

DMAC LTO Error

Description:

A Local Bus time-out (LTO) occurred while the DMAC

 

was Local Bus master.

MPU Notification:

DMAC interrupt (when enabled)

Status:

The DLTO bit is set in the DMAC Status register (address

 

$FFF40048 bit 3).

Comments:

This indicates the DMAC attempted to access a Local Bus

 

address at which there was no resource. If the TBL bit is

 

set (address $FFF40048 bit 2), the error occurred during a

 

command table access; otherwise the error occurred during

 

a data access.

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Motorola MVME1X7P manual Dmac Offboard Error, Dmac LTO Error