W90221X Winbond Electronics Corp America, W90221X Datasheet - Page 147

• Manufacturer Part Number: W90221X
• Description: Pa-risc Embedded Controller
• Manufacturer: Winbond Electronics Corp America

Device Control Register (DCR)
Port address: 0xf000037a
Bits 0-1
Bit 2
Bit 3
Bit 3
Bit 4
Bit 5
Bit 6
Bit 7
This register directly controls several output signals as well as enabling some functions. The
power-on default "0x0" sets {nSelectIn, nInit, nAutoFd, nStrobe} to {high, low, high, high}
states, and enables 8-bit data bus in output mode which are suit for "standard mode"
transferring.
W90221X version 0.6
0
0
1
Reserved
1
Reserved
Data bus output enable
Data bus is driven by PPI for forward transferring
Data bus is driven by peripheral device for reverse transferring
nAck interrupt enable
When this bit is set, a low-to-high transition on nAck line will generate
an interrupt request to CPU core.
Parallel port interface signal “ Select”
Inverted parallel port interface signal “ nSelectIn”
Parallel port interface signal “ nInit”
Inverted parallel port interface signal “ nAutoFd”
Inverted parallel port interface signal “ nStrobe”
DOE
2
NACK_IEN NSELIN#
Access type: read
3
4
NINIT
5
NAUFD#
6
Default: 0x0
NSTB#
7
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