IBM 5150 Hardware Reference Manual

Table 16. Status Register 2
BIT
NO. NAME
SYMBOL
07 -
-
06 Control Mark
CM
05
Data Error in
DO
Data Field
04 Wrong Cylinder
WC
03
Scan Equal Hit
SH
02 Scan Not
SN
Satisifed
01 Bad Cylinder BC
00
Missing Address MD
Mark in Data
Field
DESCRIPTION
Not Used. This bit is always 0 (low).
During execution of the Read Data or
Scan command, if the FDC encounters
a sector
which contains a Deleted Data
Address Mark, this flag is set.
If the FOC detects a CRC error in the
data then this flag is set.
This bit is related with the NO bit, and
when the contents of C on the medium
are different from that stored in the
ID Register, this flag is set.
During execution of the Scan command,
if the condition of "equal" is satisfied,
this flag is set.
During execution of the Scan command,
if the FDC cannot find a sector on the
cylinder which meets the condition, then
this flag is set.
This bit is related with the NO bit, and
when the contents of C on the medium
are different from that stored in the ID
Register, and the content of C is FF, then
this flag is set.
When data is read from the medium, if
the FDC cannot find a Data Address
Mark or Deleted Data Address Mark,
then this flag is set.
2-102

IBM 5150 Specifications

General

Processor	Intel 8088
Clock Speed	4.77 MHz
RAM	16 KB - 256 KB
Manufacturer	IBM
Model	5150
Release Year	1981
Storage	5.25-inch floppy drives
Graphics	MDA or CGA
Operating System	IBM PC DOS
Ports	Cassette, keyboard
Expansion Slots	5