Motorola MVME1X7P manual Dmac VMEbus Address Counter, Dmac Byte Counter, Table Address Counter

Models: MVME1X7P

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VMEchip2

DMAC VMEbus Address Counter

ADR/SIZ

 

$FFF4003C

(32 bits)

 

 

 

 

 

BIT

31

. . .

 

0

 

 

 

 

NAME

 

DMAC VMEbus Address Counter

 

 

 

OPER

 

R/W

 

 

 

RESET

 

0 PS

 

 

 

 

 

In direct mode, this counter is programmed with the starting address of the data in VMEbus memory.

DMAC Byte Counter

ADR/SIZ

 

$FFF40040 (32 bits)

 

 

 

 

 

BIT

31

. . .

0

 

 

 

 

NAME

 

DMAC Byte Counter

 

 

 

 

 

OPER

 

R/W

 

 

 

 

 

RESET

 

0 PS

 

 

 

 

 

In direct mode, this counter is programmed with the number of bytes of data to be transferred.

Table Address Counter

ADR/SIZ

 

$FFF40044 (32 bits)

 

 

 

 

 

BIT

31

. . .

0

 

 

 

 

NAME

 

Table Address Counter

 

 

 

 

 

OPER

 

R/W

 

 

 

 

 

RESET

 

0 PS

 

 

 

 

 

In command chaining mode, this counter should be loaded by the processor with the starting address of the list of commands. This register gets reloaded by the DMAC with the starting address of the current command. The last command in a list should have bits 0 and 1 set in the next command pointer.

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Motorola MVME1X7P manual Dmac VMEbus Address Counter, Dmac Byte Counter, Table Address Counter