Advanced Step Motor

Control Chipset

MC1451A, MC1451A-E

MC1251A, MC1251A-E
MC1151A, MC1151A-E

Advanced control of up to 4 step motors
per chipset
High speed pulse and direction output
S-curve, trapezoidal, velocity contouring,
and electronic gearing trajectory modes
Optional incremental encoder feedback
Software & feature compatible with other
versions of PMD's chipset family
Available in 1, 2, or 4 axis configurations
32-bit position, velocity, acceleration and
jerk trajectory profile registers
Pulse and direction output for each axis at
up to 1.5 Mpulses/sec
On-the-fly stall detection
Two travel-limit switches per axis
External motion breakpoint per axis
Intelligent easy-to-use packet-oriented
command protocol
Programmable pulse output modes
Chipset Developer's kit available

Features

General Description

The MC1451A is a dedicated motion processor which functions
as a complete chip-based step motor controller. Packaged in a
2-IC chipset, this device performs trajectory generation and
pulse and direction signal generation for use in a wide variety of
stepper-based systems. The MC1451A provides an optional
third IC which allows incremental encoder signal input for
position verification and on-the-fly stall detection. The MC1451A
is available in a one, a two, and a four-axis configuration.

The MC1451A is functionally similar to other PMD motion
processors however it is dedicated to the control of step motors,
instead of servo motors. All of these devices provide
sophisticated trajectory generation and synchronization features
allowing the creation of complex motion sequences.

In addition to pulse and direction circuitry which can output at
up to 1.5 megapulses per second the chipset provides two limit
switches per axis, a programmable external signal breakpoint
per axis, and an 'At Rest' output signal.

The chipset is controlled by a host processor which interfaces
with the chipset via an 8-bit bi-directional port. Communications
to/from the chipset consist of packet-oriented messages. A host
interrupt line is provided so that the chipset can signal the host
when special conditions occur such as stall detection.

The chipset is packaged in 2 68-pin PLCC packages. An
optional third 44 pin PLCC chip provides encoder input. All
chips are CMOS and are powered by 5 volts.

Doc. Rev. 12.02, Nov. 1997

Typical Configuration

Host

Processor

MC1451A

(I/O & CP

& ENC)

Axis 1

Axis 2

Axis 3

Axis 4

Amp

(MC1451A only)

(MC1451A, MC1251A

only)

Performance Motion Devices, Inc. 12 Waltham St. Lexington, MA 02421 tel: 781.674.9860 fax: 781.674.9861 www.pmdcorp.com

Table of Contents

Product Family Overview....................................... Page 3

Introduction........................................................... Page 3
Family Summary................................................... Page 3

Electrical Characteristics....................................... Page 4

Absolute Maximum Ratings.................................. Page 5
Operating Ratings................................................. Page 5
DC Electrical Characteristics ................................ Page 5
AC Electrical Characteristics ................................ Page 5
I/O Timing Diagrams............................................. Page 7

Pinouts .................................................................... Page 11

MC1451A.............................................................. Page 11
MC1251A, MC1151A............................................ Page 12
Pin Descriptions.................................................... Page 13

Theory of Operations ............................................. Page 17

Trajectory Profile Generation................................ Page 18

S-curve Point to Point ....................................... Page 19
Trapezoidal Point to Point................................. Page 20
Velocity Contouring........................................... Page 20
Electronic Gear................................................. Page 21

Trajectory Control ................................................. Page 21

Halting The Trajectory ...................................... Page 21
Motion Complete Status ................................... Page 22

Parameter Loading & Updating ............................ Page 22

Manual Update ................................................. Page 22
Breakpoints....................................................... Page 23
External Breakpoints and Homing .................... Page 23
Disabling Automatic Profile Update .................. Page 24

Travel Limit Switches............................................ Page 24
Axis Timing ........................................................... Page 24
Host Communications .......................................... Page 25

Electrical Interface ............................................ Page 25

Packet Format...................................................Page 25
Packet Checksum .............................................Page 26
Illegal Commands .............................................Page 26
Command Errors...............................................Page 26
Axis Addressing.................................................Page 26

Axis Status ............................................................Page 27

Status Word ......................................................Page 27
Miscellaneous Mode Status Word.....................Page 27

Host Interrupts.......................................................Page 28
Pulse & Direction Signal Generation .....................Page 29

Pulse Generation Control...........................................Page 29
At Rest Indicator.........................................................Page 29

Encoder Position Feedback ..................................Page 29

Stall Detection............................................................Page 30
Position Error .............................................................Page 30
Recovering From A Motion Error ...............................Page 30

Host Commands .....................................................Page 32

Command Summary .............................................Page 32
Command Reference ............................................Page 34

Axis Control.......................................................Page 34
Profile Generation .............................................Page 35
Parameter Update.............................................Page 39
Interrupt Processing ..........................................Page 41
Status/Mode ......................................................Page 42
Pulse Generation ..............................................Page 43
Encoder.............................................................Page 44
Miscellaneous ...................................................Page 45

Application Notes ...................................................Page 48

ISA bus interfacing ................................................Page 48

Performance Motion Devices, Inc. does not assume any responsibility for use of any circuitry described in this manual, nor does it make
any guarantee as to the accuracy of this manual. Performance Motion Devices, Inc. reserves the right to change the circuitry described in
this manual, or the manual itself, at any time.

The components described in this manual are not authorized for use in life-support systems without the express written permission of
Performance Motion Devices, Inc.

Product Family Overview

MC1401 series

MC1231 series

MC1241 series

MC1451 series

# of axes

4, 2, or 1

2 or 1

4, 2, or 1

Motors Supported

DC Servo

Brushless Servo

Stepper

Encoder Format

Incremental (no dash version)

and Parallel ('-P' version)

Incremental

Incremental*

Output Format

DC servo

Sinusoidally

commutated

Microstepping

Pulse and Direction

S-curve profiling

Yes

Electronic gearing

Yes

On-the-fly changes

Yes

Limit switches

Yes

PID & feedforward

Yes

PWM output

Yes

DAC-compatible output

Yes

Pulse & direction output

Yes

Index & Home signal

Yes

Chipset p/n's

MC1401A, MC1401A-P (4 axes)
MC1201A, MC1201A-P (2 axes)
MC1101A, MC1101A-P (1 axis)

MC1231A (2 axes)
MC1131A (1 axis)

MC1241A (2 axes)
MC1141A (1 axis)

MC1451A, MC1451A-E (4 axes)
MC1251A, MC1251A-E (2 axes)
MC1151A, MC1151A-E (1 axis)

Developer's Kit p/n's:

DK1401A, DK1401A-P

DK1231A

DK1241A

DK1451A

* optional using third I.C. ('-E' version)

Introduction

This manual describes the operational characteristics of the MC1451A,
MC1251A, MC1151A, MC1451A-E, MC1251A-E, and MC1151A-E
Motion Processors. These devices are members of PMD's 1st
generation motion processor family, which consists of 16 separate
products organized into four groups.

Each of these devices are complete chip-based motion controllers.
They provide trajectory generation and related motion control functions.
Depending on the type of motor controlled they provide servo loop
closure, on-board commutation for brushless motors, and high speed
pulse and direction outputs. Together these products provide a
software-compatible family of dedicated motion processor chips which
can handle a large variety of system configurations.

Each of these chips utilize a similar architecture, consisting of a high-
speed DSP (Digital Signal Processor) computation unit , along with an
ASIC (Application Specific Integrated Circuit). The computation unit
contains special on-board hardware such as a multiply instruction that
makes it well suited for the task of motion control.

Along with a similar hardware architecture these chips also share most
software commands, so that software written for one chipset may be re-
used with another, even though the type of motor may be different.

This manual describes the operation of the MC1451A, MC1251A,
MC1151A, MC1451A-E, MC1251A-E, and MC1151A-E chipsets. For
technical details on other members of PMD's first generation
motion processors see the corresponding product manual.

Family Summary

MC1401 series (MC1401A, MC1201A, MC1101A, MC1401A-P,
MC1201A-P, MC1101A-P) - These chipsets take in incremental
encoder signals (standard version) or parallel word encoder signals
(-P version) and output a motor command in either PWM or DAC-
compatible format. These chipsets come in 1, 2 or 4 axis versions
and can be used with DC brushed motors, or brushless motors using
external commutation.

MC1231 series (MC1231A, MC1131A) - These chipsets take in
incremental quadrature encoder signals and output sinusoidally
commutated motor signals appropriate for driving brushless motors.
They are available in one or two axis versions. Depending on the
motor type they output two or three phased signals per axis in either
PWM or DAC-compatible format.

MC1241 series (MC1241A, MC1141A) - These chipsets provide
internal microstepping generation for stepping motors. They are
available in a one or a two-axis version. Two phased signals are
output per axis in either PWM or DAC-compatible format. An
incremental encoder signal can be input to confirm motor position.

MC1451 series (MC1451A, MC1251A, MC1151A, MC1451A-E,
MC1251A-E, MC1151A-E) - These chipsets provide very high speed
pulse and direction signal output appropriate for driving step motor-
based systems. They are available in a one, two, or four-axis version
and are also available with quadrature encoder input.

Each of these chipsets has an associated Chipset Developer's
Kit available for it. For more information contact your PMD
representative.

Electrical Characteristics

Overview

The MC1451A-consists of either two 68 pin PLCC's (standard version),
or these same two I.C.s with an additional 44 pin PLCC for incremental
encoder feedback (-E version). All of these devices are fabricated in
CMOS. The two 68 pin PLCCs are known as the I/O and the CP chips.
The 44-pin PLCC is known as the ENC chip.

The Peripheral Input/Output IC (I/O chip) is responsible for interfacing
to the host processor and for generating the high speed pulse and
direction output. The Command Processor IC (CP chip) is responsible
for all host command, trajectory, and related computations. The ENC
chip is responsible for incremental encoder feedback.

The following figure shows a typical system block diagram, along with
the pin connections between the I/O chip, CP chip, and ENC chip if it is
used.

Encoder

(1-4 axis)

Host

Processor

I/O

Data4-11

I/OAddr0-3

I/OWrite

I/OCntrl0-3

ClkOut

Amplifier

(1-4 axis)

Motor

(4 axis)

ENC

Data4-11

I/OAddr0-3

I/OWrite

I/OCntrl0-3

ClkOut

Use of the ENC chip does not require a special version of the I/O or CP
chips. The CP chip automatically recognizes the presence or absence
of the ENC chip and functions accordingly.

The CP, I/O, and ENC chip (if used) form a complete chipset and
function together as one integrated motion processor. The major
components connected to the chipset are the step & direction
compatible amplifier (4, 2, or 1 axes), the optional encoder feedback
channels (4, 2, or 1 axes), and the host processor.

The chipset's pulse and direction output signals are connected to the
motor amplifier. Using this scheme the direction bit indicates whether
the motor should move in the positive or negative direction, and the
pulse signal indicates the desired motor speed. Pulse and direction
output is compatible with a wide variety of full, half, and microstepping
amplifiers.

Using the -E chipset parts it is possible to input quadrature encoder
feedback to the chipset. The encoder signals consist of the A and B
quadrature signals from the encoder.

The host processor is interfaced via an 8-bit bi-directional bus and
various control signals. Host communication is coordinated by a
ready/busy signal, which indicates when communication is allowed.

Interconnections between the I/O and the CP chip consist of a data bus
(8 bits) and various control and synchronization signals.
Interconnections between the CP and the ENC chip (if used) also
consist of a data bus (10 bits) and various control and synchronization
signals. Many of these signals are common between the I/O, CP, and
the ENC chips although there are no direct connections between just
the ENC and the I/O chip. The following table summarizes the signals
that must be interconnected for the chipset to function properly. For
each listed signal the I/O chip pin on the left side of the table is
connected to the CP chip pin in the middle which is connected to the
ENC chip pin on the right side.

I/O Chip
Signal
Name

I/O
Chip
Pin

CP Chip
Signal
Name

CP
Chip
Pin

ENC Chip
Signal
Name

ENC
Chip
Pin

Data2

CPData2

Data3

CPData3

CPData4

Data4

CPData4

CPData5

Data5

CPData5

CPData6

Data6

CPData6

CPData7

Data7

CPData7

CPData8

Data8

CPData8

CPData9

Data8

CPData9

CPData10

Data10

CPData10

CPData11

Data11

CPData11

CPAddr0

I/OAddr0

CPAddr0

CPAddr1

I/OAddr1

CPAddr2

I/OAddr2

CPAddr2

CPAddr3

I/OAddr3

CPAddr3

CPCntr0

I/OCntr0

CPCntr0

CPCntr1

I/OCntr1

CPCntr2

I/OCntr2

CPCntr3

I/OCntr3

CPWrite

I/OWrite

CPWrite

CPClk

ClkOut

CPClk

CPReset

Reset

For a complete description of all pins see the 'Pin Descriptions'
section of this manual.

Unless specifically noted otherwise, the term 'MC1451' or
'MC1451A' refers to the MC1451A, MC1251A, MC1151A, MC1451A-
E, MC1251A-E, and MC1151A-E Motion Processors.

Absolute Maximum Ratings

Unless otherwise stated, all electrical specifications are for both
the I/O and CP chips.

Storage Temperature, Ts .................... -55 deg. C to +150 deg. C
Supply Voltage, Vcc ............................ -0.3 V to +7.0 V
Power Dissipation, Pd ......................... 650 mW (I/O and CP
combined)

Operating Ratings

Operating Temperature, Ta .................0 deg. C to +70 deg. C*
Nominal Clock Frequency, Fclk ...........25.0 Mhz
Supply Voltage, Vcc.............................4.75 V to 5.25 V

* Industrial and Military operating ranges also available. Contact your
PMD representative for more information.

DC Electrical Characteristics

(Vcc and Ta per operating ratings, Fclk = 25.0 Mhz)

Symbol

Parameter

Min.

Max.

Units

Conditions

Vcc

Supply Voltage

4.75

5.25

Idd

Supply Current

100

open outputs

Input Voltages

Vih

Logic 1 input voltage

2.0

Vcc + 0.3

Vil

Logic 0 input voltage

-0.3

0.8

Vihclk

Logic 1 voltage for clock pin

(ClkIn)

3.0

Vcc+0.3

Vihreset

Logic 1 voltage for reset pin

(reset)

4.0

Vcc+0.3

Output Voltages

Voh

Logic 1 Output Voltage

2.4

@CP Io = 300 uA

@I/O Io = 4 mA

Vol

Logic 0 Output Voltage

0.33

@CP Io = 2 mA
@I/O Io = 4 mA

Iout

Tri-State output leakage current

-20

0 < Vout < Vcc

Iin

Input current

-50

0 < Vi < Vcc

Iinclk

Input current ClkIn

-20

0 < Vi < Vcc

AC Electrical Characteristics

(see reference timing diagrams)
(Vcc and Ta per operating ratings; Fclk = 25.0 Mhz)
(~ character indicates active low signal)

Timing Interval

Min.

Max.

Units

Encoder and Index Pulse Timing
Motor-Phase Pulse Width

1.6

Dwell Time Per State

0.8

Index Pulse Setup and Hold
(relative to Quad A and Quad B low)

Reset Timing
Stable Power to Reset

0.25

Sec

Reset Low Pulse Width

1.0

Clock Timing
Clock Frequency (Fclk)

6.7

25.6

Mhz

Clock Pulse Width

19.5

75 (note 2)

Clock Period

149 (note 2)

Электронный компонент: MC1151A

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