UL
®
LSI/CSI
LSI Computer Systems, Inc. 1235 Walt Whitman Road, Melville, NY 11747
RS2
RS1
RS0
CHS1
CHS0
NC
NC
RD/
CS/
LS7566
(631) 271-0400 FAX (631) 271-0405
July 2005
A3800
24-BIT FOUR-AXES QUADRATURE COUNTER
FEATURES:
• Read/write registers for count and I/O modes.
Count modes include: Non-quadrature (Up/Down), Quadrature
(x1, x2, x4), Free-run, Non-recycle, Modulo-n and Range limit
• Separate mode-control registers for each axis
• Interrupt output and interrupt mask register.
• 40 MHz count frequency, 5V
20 MHz count frequency, 3V
• Sets of 24-bit counters, preset registers, comparators and
output latches and 8-bit status registers for each axis
• Digital filtering of the input quadrature clocks for
noise immunity.
• 3-state Octal I/O bus
• 3V to 5.5V operating voltage range
• LS7566-TS (TSSOP) -See Figure 1-
GENERAL DESCRIPTION:
The LS7566 consists of four identical modules of 24-bit pro-
grammable counters with direct interface to incremental encod-
ers. The modules can be configured to operate as quadrature-
clock counters or non-quadrature up/down counters. In both
quadrature and non-quadrature modes, the modules can be fur-
ther configured into free-running, non-recycle, modulo-n and
range-limit count modes. The mode configuration is made
through two 8-bit read/write addressable control registers, MDR0
and MDR1. Data can be ported to a 24-bit preset register PR, or-
ganized in directly addressable (write-only) byte0 [PR0] byte1
[PR1] and byte2 [PR2] segments. PR can be transferred to the
24-bit counter CNTR either by instruction to MDR1 or by hard-
ware input control. A 24-bit digital comparator perpetually checks
for the equality of the CNTR and the PR and can be used to set
an output flag when the equality occurs. For reading the CNTR,
its instantaneous value can be transferred to a 24-bit output latch
OL, either by instruction to MDR1 or by hardware input control.
The OL in turn can be read in directly addressable (read-only)
byte0 [OL0], byte1 [OL1] and byte2 [OL2] segments. An address-
able (read-only) Octal status register STR, stores the count re-
lated status information such as CNTR overflow, underflow,
count direction etc. Data communication for read/write is per-
formed through an Octal 3-state parallel I/O bus
.
REGISTER DESCRIPTION:
PIN ASSIGNMENT
- Top View
1
2
3
4
5
6
7
8
9
48 x0FLGa
47 x0FLGb
46 x1FLGa
45 INT/
44 NC
43 GND
42 x1FLGb
41 x2FLGa
40 x2FLGb
WR/ 10
DB0 11
DB1 12
DB2 13
DB3 14
DB4 15
DB5 16
DB6 17
DB7 18
NC 19
NC 20
PCK
21
GND 22
x0INDX
23
x0A 24
LSI
LS7566
39 x3FLGa
38 x3FLGb
37 VDD
36 x3B
35 x3A
34 x3INDX
33 x2B
32 x2A
31 NC
30 NC
29 x2INDX
28 x1B
27 x1A
26 x1INDX
25 x0B
Following is a list of the hardware registers. There are four
sets of registers, with name prefixes x0 through x3 to refer
to axes x0 through x3.
FIGURE 1
The information included herein is believed to be
accurate and reliable. However, LSI Computer Systems,
Inc. assumes no responsibilities for inaccuracies, nor for
any infringements of patent rights of others which may
result from its use.
7566-072205-1
LSI [ LSI COMPUTER SYSTEMS ]
