Read Buffer (E4H) - IBM DBCA-204860 - Travelstar 4.8 GB Hard Drive Specifications

12.11 Read Buffer (E4h)

C o m m a n d B l o c k O u t p u t R e g i s t e r s
R e g i s t e r
D a t a
F e a t u r e
S e c t o r C o u n t
S e c t o r N u m b e r
C y l i n d e r L o w
C y l i n d e r H i g h
D e v i c e / H e a d
C o m m a n d
E r r o r R e g i s t e r
7 6 5
C R C U N C 0 I D N
0 0 0
Figure 76. Read Buffer Command (E4h)
The Read Buffer command transfers a sector of data from the sector buffer of device to the host.
The sector is transferred through the Data Register 16 bits at a time.
The sector transferred will be from the same part of the buffer written to by the last Write Buffer command.
The contents of the sector may be different if any reads or writes have occurred since the Write Buffer
command was issued.
7 6 5 4 3 2 1 0
1 1 D
1 1 1 0 0 1 0 0
4 3 2 1 0
0 A B T T 0 N A M N
0 0 V 0 0
C o m m a n d B l o c k I n p u t R e g i s t e r s
R e g i s t e r 7 6 5 4 3 2 1 0
D a t a
E r r o r . . . S e e B e l o w . . .
S e c t o r C o u n t
S e c t o r N u m b e r
C y l i n d e r L o w
C y l i n d e r H i g h
D e v i c e / H e a d
S t a t u s . . . S e e B e l o w . . .
S t a t u s R e g i s t e r
7 6 5 4 3
B S Y R D Y D F D S C D R Q C O R I D X E R R
0 V 0
Command Descriptions
2 1 0
0 V
117