PC87311AVF datasheet(40/78 Pages) NSC

40 / 78 page

40 FDC Command Set Description (Continued)

TABLE 4-16 Verify Command Result Phase Table

SCEOT Value

Termination Result

DTL used (should be FF hex)

No Errors

EOT s

Sectors per Side

DTL used (should be FF hex)

Abnormal Termination

EOT l

Sectors per Side

SC s

Sectors per Side

No Errors

AND

SC s EOT

SC l

Sectors Remaining

Abnormal Termination

SC l EOT

DTL used (should be FF hex)

No Errors

EOT s

Sectors per Side

DTL used (should be FF hex)

Abnormal Termination

EOT l

Sectors per Side

SC s

Sectors per Side

No Errors

AND

SC s EOT

SC s (EOT c 2)

No Errors

AND

EOT s

Sectors per Side

SC l (EOT c 2)

Abnormal Termination

Note 1

Sectors per Side e number of formatted sectors per each side of the disk

Note 2

Sectors Remaining e number of formatted sectors left which can be read which includes side 1 of the disk if the MT bit is set to 1

Note 3

If MT e 1 and the SC value is greater than the number of remaining formatted sectors on side 0 verifying will continue on side 1 of the disk

Having finished writing the sector the controller will contin-

ue reading the next logical sector unless one or more of the

following termination conditions occurred

1 The DMA controller asserted TC The IC bits in ST0 are

set to Normal Termination

2 The last sector address (of side 1 if MT was set) was

equal to EOT The EOT bit in ST1 is set The IC bits in

ST0 are set to Abnormal Termination This is the expect-

ed condition during Non-DMA transfers

3 Underrun error The OR bit in ST1 is set The IC bits in

ST0 are set to Abnormal Termination If the mP cannot

service a transfer request in time the last correctly writ-

ten byte will be written to the disk

If MT was set in the Opcode command byte and the last

sector of side 0 has been transferred the controller will then

continue with side 1

4224 Write Deleted Data

The Write Deleted Data command receives data from the

host and writes logical sectors containing a Deleted Data

AM to the selected drive This command is identical to the

Write Data command except that a Deleted Data AM is writ-

ten to the Data Field instead of a Normal Data AM

50 FDC Functional Description

The PC87311A12 is software compatible with the DP8473

and 82077 floppy disk controllers Upon a power on reset

the 16-byte FIFO will be disabled Also the disk interface

outputs will be configured as active push-pull outputs which

are compatible with both CMOS inputs and open-collector

resistor terminated disk drive inputs The FIFO can be en-

abled with the Configure command The FIFO can be very

useful at the higher data rates with systems that have a

large amount of DMA bus latency or with multi-tasking sys-

tems such as the EISA or MCA bus structures

The FDC will support all the DP8473 Mode command fea-

tures as well as some additional features These include

control over the enabling of the FIFO for reads and writes a

Non-Burst mode for the FIFO a bit that will configure the

disk interface outputs as open-drain outputs and pro-

grammability of the DENSEL output

51 MICROPROCESSOR INTERFACE

The FDC interface to the microprocessor consists of the

A9 – A3 AEN RD and WR lines which access the chip for

reads and writes the data lines D7 – D0 the address lines

A2 – A0 which select the appropriate register (see Table

3-1)

the IRQ6 signal

and the DMA interface signals

PC87311AVF Datasheet(PDF) 40 Page - National Semiconductor (TI)

PC87311AVF Datasheet(HTML) 40 Page - National Semiconductor (TI)

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78

Datasheet Download

Link URL