Arm Enterprises IM-AD1 manual Stepper motor interface, Functional description

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Hardware Reference

3.5Stepper motor interface

The IM-AD1 provides four stepper motor interfaces. Two of these, Step 1 and Step 2, are provided with on-board motor drivers for bipolar motors. The remaining two, Step

3and Step 4, provide logic-level signals that are connected to two 10-pin headers. This enables you to connect to off-board motor drivers.

3.5.1Functional description

The on-board stepper motor drivers comprise a L6506 current controller and L298 bridge drivers. These are controlled directly by outputs from the logic module and are configured to drive bipolar motors. Figure 3-5shows the architecture of one stepper motor driver.

STEP1_VSS

	STEP1_ENA
Socket	STEP1_ENB
Socket	STEP1_PH2
	STEP1_PH1		L298
			L298
IM	STEP1_PH3	L6506	(U24)
IM	STEP1_PH3	(U23)
	STEP1_PH4	(U23)
	STEP1_PH4

STEP1_O1

STEP1_O2

STEP1_O3

STEP1_O4

J19

	motor	windings
	Stepper	windings
	Stepper

STEP_GND

Figure 3-5 Stepper motor drivers (Step 1)

The L298 contains driver circuitry for two bridges, and each bridge has separate enable signals. The enable signals and four phase drive signals are supplied by a stepper motor controller instantiated in the logic module FPGA (see Chapter 4 Reference Design Example). The controller logic uses the 4MHz IM_CLK signal divided to provide a step clock.

The L6506 uses a chopper circuit, operating at a frequency of 21kHz, to control the current on the phase drive signals to the stepper motor. A 0.1Ω sense resistor is provided to generate a voltage drop that is proportional to the motor current. The sense voltage is compared against a reference voltage of 0.15V that is supplied to the L6506 by a resistive divider. When the reference voltage is reached, the phase drive signals are turned off until the start of the next chopper period.

3-8

Copyright © 2001-2003. All rights reserved.

ARM DUI 0163B

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Contents Integrator/IM-AD1 Integrator/IM-AD1 User GuideConformance Notices Copyright 2001-2003. All rights reserved Integrator/IM-AD1 User Guide Chapter IntroductionAppendix a Signal Descriptions Preface Intended audience Using this bookAbout this book ARM publications Typographical conventionsFurther reading Third-party documents Feedback on the Integrator/IM-AD1 FeedbackFeedback on this document Xii Introduction About the Integrator/IM-AD1 ARM DUI 0163BIntegrator/IM-AD1 layout Interface module features and architecture FeaturesIntegrator/IM-AD1 block diagram ArchitectureConfig LED Links and LEDsCare of modules Introduction Copyright 2001-2003. All rights reserved Getting Started Fitting the interface module Assembled Integrator development systemSetting up the logic module Switch 2 Closed Switch 3 Open Switch 4 OpenRunning the test software Hardware Reference Hardware Reference Serial interface signal assignment Signal name ConnectorUart interface DescriptionSerial connector pinout Serial connector signal assignment Pin J18 Type DescriptionSPI signals Signal SPIPWM interface signals Signal PWM interfaceShows the signal assignment PWM connector signals Pin J14 J10 DescriptionStepper motor interface Functional descriptionStepper motor interface signal summary Therefore, with a 0.1Ω sense resistor fittedStepper motor connectors Stepper motor interface signalsStepper motor connector signals Pin J19 J23 Description VSSGpio connectors J16 and J17 GpioHardware Reference Buffer Can interfaceU13 Can interface signal assignment Signal IMBBANK30 IMBBANK28IMBBANK29 Can connector signal assignments Pin GNDADC and DAC interfaces 10 ADC and DAC interface architectureIMABANK48 IMABANK49IMABANK50 IMABANK5111shows the pinout of the ADC interface connector J1 12 shows the pinout of the DAC interface connector J2 Hardware Reference Copyright 2001-2003. All rights reserved Reference Design Example Example architecture About the design exampleAbout PrimeCells Vhdl file descriptions File DescriptionExample memory map Address assignment of logic modules Integrator system memory mapIntegrator/IM-AD1 memory map Device Address Integrator/IM-AD1 memory mapLogic module addresses Position Bits Stack Stepperb GpioaGpiob SsramOffset address Name Type Function Example APB register peripheralLogic module registers Oscillator divisor registers VDW LMOSCx registers Bits Name Access FunctionRDW Bits Name Access Function Oscillator lock registerUser LEDs control register Push button interrupt registerSwitches register Uart SPI chip select register SPICS2SPICS1 SPICS0Synchronous serial port PWM controller Offset Name Access Function Address Stepper motor peripheralCont CountStepper x control register DIR DocountSinglestep Stepx count register Stepx speed registerRead data output pins Address offset Name Access Size FunctionData output set register Read data input registerData direction Gpio direction control 1 bitSsram interface Vectored interrupt controller Interrupt sourcesInterrupt Interrupt source Source number CAN1Reference Design Example Can reset control register CanresetCan controller interface CANxBaseADC and DAC interface 16 ADC and DAC interface registersAdcstatus ADC2BUSYBits Name Function Peripheral information block18 PIB entry format Signal Descriptions Expa Table A-1 AHB signal assignment Pin label Signal DescriptionExpb Table A-2 Expb signal description Pin label Name DescriptionExpim LM-EP20K1000E Description Table A-3 Expim signal descriptionsLabel Logic analyzer connector Figure A-4 J7 pin locationsTable A-4 J7 connector pinout Signal Pin CLK1Figure A-5 Multi-ICE connector pinout Multi-ICE JtagMechanical Specification Figure B-1 Board dimensions top view Mechanical informationFigure B-2 Bottom board dimensions viewed from top side DB9STRAIGHT FCI Connector referenceDB9DUAL Glossary Multi-ICESynchronous Serial Port Index ADC CanDAC GpioLmleds Lmlock LMOSC1 Expa A-2Gpiodataclr Gpiodatain Gpiodataout Gpiodataset Gpiodirn