Chapter 3 - MACSI Host Interface

Address modifier

This field contains the VMEbus address modifier used for the transfer. Refer to your system documentation for possible values for this field.

Memory type (MT)

This 2-bit field specifies the width of the data transfers. Permitted values are:

Table 3-17. Memory Type

Bit 9

Bit 8

Memory Type

 

 

 

 

 

 

0

0

Reserved (or Short I/O)

 

 

 

0

1

16 bit transfers

 

 

 

1

0

32 bit transfers

 

 

 

1

1

Reserved

 

 

 

Transfer type (TT)

This 2-bit field specifies the type of data transfer to be performed. Permitted values are:

Table 3-18. Transfer Type

Bit 11

Bit 10

Transfer Type

 

 

 

 

 

 

0

0

Normal Type

 

 

 

0

1

Block Mode

 

 

 

1

0

Reserved

 

 

 

1

1

VME D64 Block

 

 

 

Direction bit (DIR)

This bit is ignored.

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