w83c554f Winbond Electronics Corp America, w83c554f Datasheet - Page 127

• Manufacturer Part Number: w83c554f
• Description: System I/o Controller With Pci Arbiter & Ultradma/33 Ide Controller
• Manufacturer: Winbond Electronics Corp America

W83C554F
Port x Drive x Control Registers
Function:
WINBOND ELECTRONICS CORP. AMERICA
These registers control the features of the four devices connected to the two ports. All four registers are
identical and control the features of only one device. The Port 0 Drive 0 Control Register (44h-47h)
controls the features of the master drive attached to the primary port. The Port 0 Drive 1 Control Register
(48h-4Bh) controls the features of the slave drive attached to the primary port. The Port 1 Drive 0 Control
Register (4Ch-4Fh) controls the features of the master drive attached to the secondary port. The Port 1
Drive 1 Control Register (50h-53h) controls the features of the slave drive attached to the secondary port.
The command timing controls only affect 16-bit and 32-bit accesses.
Calculations (refer to Table 4-4):
CMD ON TIME programmed value = (DIOR#/DIOW# 16-bit min+29) / 30ns clock - 1, after
removing all digits to the right of the decimal point (see Table 4-4).
CMD OFF TIME programmed value = ((Cycle Time minimum – (CMD ON TIME programmed value
+ 1) * 30ns + 29)) / 30ns clock -1, after removing all digits to the right of the decimal point (see Table
4-4).
CMD ON TIME = Bits [12:8] of Port x Control x Registers , which are the registers of Configuration
Space 44h-54h.
CMD OFF TIME = Bits [4:0] of Port x Control x Registers , which are the registers of Configuration
Space 44h-54h.
UltraDMA Enable and Mode select
Register Information
125