CL-PD6722 datasheet(33/128 Pages) CIRRUS

33 / 128 page

CL-PD6710/’22

ISA–to–PC-Card Host Adapters

May 1997

PRELIMINARY DATA SHEET v3.1

OPERATION REGISTERS

The CL-PD67XX internal registers are accessed through a pair of Operation registers — an Index register

and a Data register. The Index register is accessed at address 03E0h, and the Data register is accessed

at 03E1h.

5.1

Index

The Data register is accessed at 03E1h.

Bits 5:0 — Register Index

These bits determine which of the 64 possible socket-speciﬁc registers will be accessed when the

Data register is next accessed by the processor. Note that some values of the Register Index ﬁeld

are reserved (see Table 5-1).

Bit 6 — Socket Index

This bit determines which set of socket-speciﬁc registers is currently selected. When this bit is ‘0’,

a Socket A register is selected. When this bit is ‘1’, a Socket B register is selected. Note that the

CL-PD6710 supports one socket, and the CL-PD6722 supports two sockets.

Bit 7 — Device Index

In systems where two CL-PD67XXs are used, this bit differentiates between them.

The Index register value determines which internal register should be accessed (read or written) in

response to each CPU access of the Data register. Each of the possible PC Card sockets is allocated 64

of the 256 locations in the internal register index space.

Figure 5-1. Device/Socket/Register Index Space

When viewed as a 8-bit value, the contents of the Index register completely specify a single internal-reg-

ister byte. For example, when the value of this register is in the range 00h–3Fh, a Socket A register is

selected (Socket Index bit is ‘0’), and when the value of this register is in the range 40h–7Fh, a Socket B

back only the upper data byte when 16-bit reads occur at 3E0h.

Index: n/a

Bit 7

Bit 6

Bit 5

Bit 4

Bit 3

Bit 2

Bit 1

Bit 0

Device Index

Socket Index

RW:0

RW:000000

Socket B Registers

Socket A Registers

00h

3Fh

40h

80h

7Fh

FFh

Socket D Registers

Socket C Registers

Possible with two CL-PD67XXs

CL-PD6722 Datasheet(PDF) 33 Page - Cirrus Logic

CL-PD6722 Datasheet(HTML) 33 Page - Cirrus Logic

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 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL