smc256af Numonyx, smc256af Datasheet - Page 42

• Manufacturer Part Number: smc256af
• Description: 32 Mbyte, 64 Mbyte, 128 Mbyte, 256 Mbyte And 512 Mbyte 3.3 V / 5 V Supply Compactflash? Card
• Manufacturer: Numonyx

Software interface
7.4
Table 38.
42/82
–
REG
0
0
0
0
0
0
0
0
0
0
A9 to A4
1F(17)h
1F(17)h
1F(17)h
1F(17)h
1F(17)h
1F(17)h
1F(17)h
1F(17)h
3F(37)h
3F(37)h
I/O primary and secondary address configurations
(conf = 2,3)
When the system decodes the primary and secondary address configurations, the registers
are accessed in the block of I/O space as shown in
As for the memory mapped addressing, register 0 is accessed with –CE1 Low and –CE2
Low (and A0 Don’t care) as a word register on the combined odd and even data bus (D15 to
D0). This register may also be accessed with –CE1 Low and –CE2 High, by a pair of byte
accesses to offset 0. The address space of this word register overlaps the address space of
the error and feature bytewide registers at offset 1. When accessed twice as byte register
with –CE1 Low, the first byte is the even byte of the word and the second is the odd byte. A
byte access to register 0 with –CE1 High and –CE2 Low accesses the error (read) or feature
(write) register.
Primary and secondary I/O decoding
A3
0
0
0
0
0
0
0
0
0
0
A2
0
0
0
0
1
1
1
1
1
1
A1
0
0
1
1
0
0
1
1
1
1
A0
0
0
1
0
0
1
0
1
1
1
Select Card/Head register
Alternate Status register
Sector Number register
Drive Address register
Cylinder High register
Sector Count register
Cylinder Low register
Even Data register
Status register
Error register
–
IORD=0
Table
38.
Select Card/Head register
Sector Number register
Device Control register
Cylinder High register
Sector Count register
Cylinder Low register
Even Data register
Command register
Feature register
–
Reserved
IOWR=0
SMCxxxAF