NCT6627UD Nuvoton Technology Corporation of America, NCT6627UD Datasheet - Page 104

• Manufacturer Part Number: NCT6627UD
• Manufacturer: Nuvoton Technology Corporation of America

Specifications of NCT6627UD

• Lead Free Status / Rohs Status: Supplier Unconfirmed

The W83627UHG FDC is capable of performing twenty commands. Each command is initiated by a multi-byte
transfer from the microprocessor, and the result may be a multi-byte transfer back to the microprocessor. Each
command consists of three phases: command, execution, and result.
Command
The microprocessor issues all required information to the controller to perform a specific operation.
Execution
The controller performs the specified operation.
Result
After the operation is completed, status information and other housekeeping information are provided to the
microprocessor.
The next section introduces each of the commands.
Command Symbol Descriptions:
C:
D:
DIR:
DS0:
DS1:
DTL:
EC:
EFIFO:
EIS:
EOT:
FIFOTHR:
GAP:
GPL:
H:
HDS:
HLT:
HUT:
LOCK:
MFM:
MT:
N:
NCN:
ND:
9.1.6 FDC Commands
Cylinder Number 0 – 256
Data Pattern
Step Direction
DIR = 0: step out
DIR = 1: step in
Disk Drive Select 0
Disk Drive Select 1
Data Length
Enable Count
Enable FIFO
Enable Implied Seek
End of Track
FIFO Threshold
Gap Length Selection
Gap Length
Head Number
Head Number Select
Head Load Time
Head Unload Time
Lock EFIFO, FIFOTHR, and PTRTRK bits to prevent being affected by software reset
MFM or FM Mode
Multitrack
The number of data bytes written in a sector
New Cylinder Number
Non-DMA Mode
-95-
W83627UHG/NCT6627UD
Publication Release Date: October 26, 2010
Revision 1.7