PCB Design and Layout Guidelines | Atmel SpW-10X manual

SpW-10X

SpaceWire Router

User Manual

12.2 PCB DESIGN AND LAYOUT GUIDELINES

PCB design and layout guide lines are provided in this section.

12.2.1 CLK

1.Series termination should be used on the CLK signal.

2.Stubs on the CLK signal shall not be used.

Ref.: UoD_SpW-10X_

UserManual

Issue: 3.4

Date: 11th July 2008

3.Guard tracks shall be provided around the CLK signal trace connected to the ground plane approximately every 1 cm.

12.2.2 RST_N

Guard tracks shall be provided around the RST_N signal trace connected to the ground plane approximately every 1 cm.

12.2.3 Chip Test Signals

The two chip test signals TestIOEn and TestEn shall both be tied directly to the ground plane.

12.2.4 Power and Decoupling

1.Each power pin shall be decoupled to ground using a 100 nF decoupling capacitor.

2.The 100 nF decoupling capacitors shall be fitted close to the each power pin with the other end of the capacitor connected to the ground plane.

3.In addition to the 100 nF decoupling capacitors four 1 µF decoupling capacitors shall be fitted close to the SpW-10X device.

12.2.5 Ground

1.A solid ground plane shall be used.

2.The ground pins of the SpW-10X shall be directly connected to the ground plane using vias close to the SpW-10X ground pins.

12.2.6 SpaceWire

The following recommendations apply to all the SpaceWire signals from the SpW-10X device (see also section 5.2):

1. LVDS receiver termination resistor shall be as close as possible to the receiver inputs.

Preliminary

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Atmel SpW-10X user manual PCB Design and Layout Guidelines

Contents

UserManual Issue Date Th JulyUoDSpW-10X 11th July Date Issue Comments AuthorRef. UoDSpW-10X SpW-10X Contents Control Logic and Operational Modes Global Spacewire Link Control 103 138 128136 151 143150 15.16 List of Figures 100 List of Tables Able 9-7 E Xternal P ORT C ONTROL/S Tatus F Ields Introduction TERMS, Acronyms and Abbreviations Documents Ref. UoDSpW-10X UserManualDate 11th July Applicable Documents Document Number Document Title User Applications STAND-ALONE Router Node Interface Embedded Router Issue Date 11th July Expanding the Number of Router Ports Expanding the number of SpaceWire Ports SpW-10X Functional Overview Spacewire Ports External Ports Routing Control Logic and Crossbar Configuration PortRouting Table TIME-CODE Processing CONTROL/STATUS Registers Pin Signal Type Description PIN Locations VSSA2 GND PFOLVDS33Z EXTOUTDATA90 PO44F EXTOUTDATA108 PO44F EXTTIMEOUT6 PO44F Global Signals Device Interface Spacewire Signals SpW-10X SpaceWire SignalsTestIOEn TestEn DOUTMinus1 DOUTPlus2DOUTMinus2 DOUTPlus3 11th July DINPlus1 DINMinus1DINPlus2 DINMinus2 SpaceWire Input Fail Safe Resistors Lvds Receiver Fail-Safe Resistors SpW-10X External Port Interface Signals PinNo Dir Description Type External Port Data SignalsUserManual Issue Date 11th July EXT9INDATA5 Selexttime and the EXTTIMEIN70 TIME-CODE SignalsTime-Code Signals PinNo Dir Description Type Exttickout is asserted Exttickin the value on EXTTIMEIN70 isEXTTIMEIN70 input Status Interface Signals Link error indication Signals PinNo Dir Description TypePower on Configuration Normal Operation Reset Configuration Signals Configuration interface timing specification 11th July Reset Configuration Signals Dir Description Feedbdiv at resetMaps to PORTXRATE20 Maps to Porstartonreqn POWER, GROUND, PLL and Lvds Signals GeneralDecoupling Lvds Reference PLL with external components Interface Operations External Port Interface Operation External port read timing specification TIME-CODE Interface Operation Status Interface Operation Time-Code Output Interface Status Output Bits Reset Configuration Interface Operation Reset configuration interface timing specification Spacewire Router Packet Types Packet Addresses Packet Priority Mapping Packet Address Physical Port type Packet PriorityPacket Header Deletion Invalid Addresses Data Packets Command PacketsSupported Commands Read Command Issue Date Th July Read Single Address Characteristics Read Single Address Command Format SpW-10X EOP Read Incrementing Command Issue Date Th July Read Incrementing Address Characteristics Data Length MS 11th July 00h Read Modify Write Command 11 Read-Modify-Write Command Characteristics Preliminary66 RMW Read-Modify-Write example operation FEh 00h Write Command 14 Write Command Characteristics FEh 01h CRC MSB Code Command Error ResponseStatus SpW-10X Command Packet Cyclic Redundancy Check Local Source Path Address Source Path Address Field Command Packet Fill Bytes Date 11 th July Spacewire Link Control Default operating modeControl Logic and Operational Modes Auto-Start Link-Disable Automatic deactivate driver mode Deactivate driver operating mode Setting the SpaceWire port transmit data rate Txrate +1 Setting SpaceWire Transmit Data Rate TX 10MbitDIV +1 Global Spacewire Link Control Cfgstartonreq bit Start on request modeDisable on Silence mode Arbitration Packet address errorControl Logic and Routing Arbitration of packets with matching priority Arbitration of three packets with matching priority Arbitration of packets with different priority SpW-10X SpW-10X Group Adaptive Routing 10 Normal group adaptive routing 11 Group adaptive routing when other ports busy Loop-back with Self-Addressing 13 Packet Self-Addressing mode Packet Blocking Blocked destination Blocking Allowed Mode 14 Destination Node Blocked a 16 Destination Node Blocked c Watchdog timer mode 19 Destination Node Blocked Watchdog Mode c Blocking Allowed 21 Source Node Stalled a 100 101 102 Register Definitions Internal Memory MAP Register Addresses Summary 11th July Configuration Register Addresses Group Adaptive Routing Table Registers 106 Issue Date Th July GAR Table Register Description Bits Name Reset Description Read/Write Value Generic port control/status register fields Configuration Port Control/Status Register FieldsPort CONTROL/STATUS Registers Configuration port control/status register fields 11th July Bits Name Reset Description Read/Write Value 110 111 SpaceWire port control/status register bits SpaceWire Port Control/Status Register Fields 113 114 Network Discovery Register External port control/status register bitsRouter CONTROL/STATUS Registers Router Identity Register Router Control Register Router Control Register Fields 118 119 Error active Register Error Active Register Fields Time-Code Register Time-Code Register Fields Device Manufacturer and Chip ID Register Time-Code Enable Register General Purpose Register Transmit Clock Control Register 125 126 Destination Key Register Unused Registers and Register BitsEmpty packets Writing to a READ-ONLY Register Serial Signals Timing Parameters Switching CharacteristicsClock and Reset Timing Parameters External Port Timing Parameters External port input Fifo timing parameters TIME-CODE Interface Timing Parameters ERROR/STATUS Interface Timing Parameters Time-code Timectrrst interface 132 Switching Latency Latency and JitterClock Periods Router Latency Issue Date Th July SpaceWire port to SpaceWire port SpaceWire port to External portExternal port to SpaceWire port Time-code Latency Time-code Jitter 10.6.6 200M bits/s Input and Output Bit Rate Example Operating Conditions Symbol Description Value Units Electrical CharacteristicsDC Characteristics Absolute Maximum Ratings Symbol Description Value Units Absolute Maximum RatingsReliability Information Reliabilty Information Example Circuit Diagram Application Guidelines 139 PCB Design and Layout Guidelines Time-code Interface Status / Power On Configuration InterfaceExternal Ports 12.2.10 PLL PLL Layout Recommendations Anomalies and Warnings Anomalies 144 Reset Anomaly Data Strobe Reset Waveform 146 Data Strobe Disable Waveform Reset Anomaly Workarounds Parity Error Anomaly Parity Error AnomalyParity Error Action Parity Error Workaround No error end of packet inserted after parity error Technical Support Issue 3.3 to Issue Issue 3.2 to IssueIssue 3.1 to Issue Document Changes Issue 3.0 to Issue Issue 2.5 to Issue Issue 2.2 to Issue Issue 2.4 to IssueIssue 2.3 to Issue Issue 2.1 to Issue Issue 2.0 to IssueIssue 1.7 to Issue Issue 1.6 to Issue Issue 1.1 to Issue Issue 1.0 to Issue