PC97307 datasheet(107/218 Pages) NSC

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Command Phase

First Command Phase Byte

See READ DATA command for a description of these

bits starting on page 96.

Second Command Phase Byte

Bits 2-0 - Drive Select (DS1,0) and Head (HD) Select

See the description of the Drive Select bits (DS1,0) and

the Head (HD) select bit in the READ DATA command,

starting on page 96.

Bit 7 - Enable Count Control (EC)

This bit controls whether the End of Track sector num-

ber or the Sectors to read Count (SC) triggers termina-

tion of the VERIFY command.

See also, Table 5-27.

0 - Terminate VERIFY when the number of the last

sector read equals the End of Track (EOT) sector

number.

The ninth command phase byte, i.e., Sectors to

read Count (SC), is not needed and should be set

to FFh.

1 - Terminate VERIFY when number of sectors read

equals the number of sectors to read, i.e., Sectors

to read Count (SC).

Third through Eighth Command Phase Bytes

See “The READ DATA Command” on page 96.

Always set the End of Track (EOT) sector number to the

number of the last sector to be checked on each side of

the disk. If EOT is greater than the number of sectors

per side, the command terminates with an error and no

useful Address Mark (AM) or CRC data is returned.

Ninth Command Phase Byte,

Sectors to Read Count (SC)

This byte specifies the number of sectors to read. If the

Enable Count (EC) control bit (bit 7) of the second com-

mand byte is 0, this byte is not needed and should be

set to the value FFh.

Execution Phase

Data is read from the disk, as the controller checks for valid

address marks in the address and data fields.

76543210

MFM

10110

XXXX

DS1

DS0

Track Number

Head Number

Sector Number

Bytes-Per-Sector Code

End of Track (EOT) Sector Number

Bytes Between Sectors - Gap 3

Sectors to read Count (SC)

This command is identical to the READ DATA command,

except that it does not transfer data during the execution

phase. See “The READ DATA Command” on page 96.

If the Multi-Track (MT) parameter is 1 and SC is greater

than the number of remaining formatted sectors on side 0,

verification continues on side 1 of the disk.

Result Phase

Table 5-27 shows how different conditions affect the termi-

nation status.

TABLE 5-27. VERIFY Command Termination

Conditions

a. The number of formatted sectors per side of the

disk.

b. The number of formatted sectors left, which can

be read, including side 1 of the disk if MT is 1.

76543210

Result Phase Status Register 0 (ST0)

Result Phase Status Register 1 (ST1)

Result Phase Status Register 2 (ST2)

Track Number

Head Number

Sector Number

Bytes-Per-Sector Code

MT EC

Sector Count (SC) or

End of Track (EOT) Value

Termination

Status

SC should be FFh

EOT

≤ Sectors per Sidea

No Errors

SC should be FFh

EOT > Sectors per Side

Abnormal

Termination

≤ Sectors per Side

and

≤ EOT

No Errors

SC > Sectors Remainingb

SC > EOT

Abnormal

Termination

SC should be FFh

EOT

≤ Sectors per Side

No Errors

SC should be FFh

EOT > Sectors per Side

Abnormal

Termination

≤ Sectors per Side

and

≤ EOT

No Errors

≤ (EOT x 2)

and

EOT

≤ Sectors per Side

No Errors

SC > (EOT x 2)

Abnormal

Termination

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