Master Control Status Block (MCSB)

Master Control Status Block (MCSB)

The MCSB consists of a Master Status Register, which is used to report information from the controller to the host, and the Master Control Register, which provides infrequently used control functions to the host.

Table 3-2. Master Control Status Block

Master Control/Status Block

Addr

15

14

13

12

11

10

9

8

7

 

6

5

4

3

2

1

0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0x000

 

 

 

 

 

Master Status Register

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0x002

 

 

 

 

 

 

Reserved

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0x004

 

 

 

 

 

Master Control Register

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0x006

 

 

 

 

 

 

Reserved

 

 

 

 

 

 

 

 

 

to

 

 

 

 

 

 

(10 Bytes)

 

 

 

 

 

 

 

 

 

0x00F

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Master Status Register (MSR)

The MSR reports to the host whether the controller is functional or not. Two bits are used.

Table 3-3. Master Status Register

Master Status Register

Addr

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0x000

 

 

 

 

 

 

 

 

 

 

 

 

 

 

BOK

CNA

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Controller not available (CNA)

This bit is set to 1 by the controller to indicate that it is not available for receipt of a command. This condition can be caused by a controller reset.

NOTE: On the V/Ethernet 4207 Eagle, the controller was defined to be available when this bit is 0. On the 4221 Condor, controller available is signalled by the presence of Board OK.

Board OK (BOK)

If 1, this bit indicates the controller has passed power up diagnostics, and is ready to accept commands.

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