snap ethernet-based i/o units protocols and programming guide

More documents

Recommendations

Info

Bytes 0–3 Bytes 4–7 Bytes 8–11 Bytes 12–15 Bytes 16–19 Last four bytes Error Codes CHAPTER 4: USING THE IEEE 1394-BASED PROTOCOL Read Block Response Tcode = 7 destination_ID tl rt tcode pri 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 0 0 0 0 source_ID rcode reserved 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 reserved 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 data_length extended_tcode 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 data_block last quadlet of data block (padded if necessary) Response packets contain an rcode parameter, which shows whether the response is an ACK or a NAK. An rcode of 0 is an ACK; anything else is a NAK. If a NAK appears in the rcode parameter, check the Status area of the memory map (see page 105) to find out the reason for the NAK. The following table lists the error codes that may appear in the Status area of the memory map: Code (Hex) Meaning Code (Hex) 0000 No error E008 Busy 98 SNAP Ethernet-Based I/O Units Protocols and Programming Guide Meaning E001 Undefined command E009 Cannot erase flash E002 Invalid point type E00A Cannot program flash E003 Invalid float E00B Downloaded image too small E004 Powerup Clear expected E00C Image CRC mismatch E005 Invalid memory address or invalid data for the memory address E00D Image length mismatch E006 Invalid command length E00E Feature is not yet implemented E007 Reserved E00F Communications watchdog timout
CHAPTER 5 Chapter 5 Advanced Modbus Programming Introduction Opto 22 form #1460, the SNAP Ethernet-based I/O Units User’s Guide, shows basic communication with a Modbus master using Modbus/TCP. However, if you need to read and write data in other areas of the brain’s memory map not covered by the Modbus memory map, you can do so with a SNAP-UP1-ADS or SNAP-B3000-ENET brain. This chapter shows you how. This chapter assumes that you already have an understanding of Modbus/TCP programming and communications. Use this chapter in conjunction with the Open Modbus/TCP Specification and the Modicon Modbus Protocol Reference Guide, both available from Modicon, Inc., Industrial Automation Systems. Information is also available at www.modbus.org/modbus tcp.htm. NOTE: Digital-only brains do not support advanced Modbus programming. Use an analog/digital/serial brain instead. Accessing Other Data in the Brain’s Memory Map If you need to read and write data in areas of the brain’s memory map not included in the Modbus memory map, you can do so with a SNAP-UP1-ADS or SNAP-B3000-ENET brain. This section shows you how. All of the brain’s regular memory map addresses are available for reading and writing, with the exception of PID module and data logging addresses. As explained in the Modbus appendix in the SNAP Ethernet-based I/O Units User’s Guide, SNAP Ethernet-based brains use a Modbus packet inside TCP/IP. The Modbus checksum is not used; instead, the Ethernet TCP/IP link layer checksum guarantees data. The size of the packet is limited to 256 bytes. The Modbus master needs to support Class 0 commands and the following function codes: 03 06 10 Read holding registers Preset single register Preset multiple registers SNAP Ethernet-Based I/O Units Protocols and Programming Guide 99
Page 1 and 2:
SNAP ETHERNET-BASED I/O UNITS PROTO
Page 3 and 4:
Table of Contents Chapter 1: Introd
Page 5 and 6:
Non-velocity Algorithms............
Page 7 and 8:
Disconnecting......................
Page 9 and 10:
Data Logging Configuration—Read/W
Page 11 and 12:
Chapter 1 Introduction CHAPTER 1 We
Page 13 and 14:
About this Guide CHAPTER 1: INTRODU
Page 15 and 16:
For Help CHAPTER 1: INTRODUCTION If
Page 17 and 18:
FEATURE CHAPTER 1: INTRODUCTION Ema
Page 19 and 20:
CHAPTER 1: INTRODUCTION This task C
Page 21 and 22:
CHAPTER 2 Chapter 2 Overview of Pro
Page 23 and 24:
Referencing SNAP I/O Points CHAPTER
Page 25 and 26:
Analog and Digital Systems (N Brain
Page 27 and 28:
Digital-Only Systems The following
Page 29 and 30:
I/O Point Types CHAPTER 2: OVERVIEW
Page 31 and 32:
CHAPTER 2: OVERVIEW OF PROGRAMMING
Page 33 and 34:
Watchdog (Digital and Analog Points
Page 35 and 36:
Page 37 and 38:
Page 39 and 40:
Page 41 and 42:
Page 43 and 44:
Page 45 and 46:
Streaming Data CHAPTER 2: OVERVIEW
Page 47 and 48:
Logging Data Area Number of Bytes I
Page 49 and 50:
Using PID Loops What is a PID? CHAP
Page 51 and 52:
Equations Common to All Algorithms
Page 53 and 54:
Page 55 and 56:
CHAPTER 3 Chapter 3 Using the SNAP
Page 57 and 58: CHAPTER 3: USING THE SNAP ETHERNET
Page 63 and 64: Environment Visual Basic 6 Internet
Page 65 and 66: MemMap Example Code CHAPTER 3: USIN
Page 71 and 72: Return Values CHAPTER 3: USING THE
Page 73 and 74: IsOpenDone V Close V Return Values
Page 75 and 76: Digital Point Methods CHAPTER 3: US
Page 77 and 78: SetDigBankOnMask V [in] long nPts63
Page 79 and 80: Analog Bank Methods CHAPTER 3: USIN
Page 81 and 82: GetStatusWatchdogTime [out] long pn
Page 87 and 88: GetLastStreamStandardBlock (ActiveX
Page 89 and 90: CHAPTER 4 Chapter 4 Using the IEEE
Page 91 and 92: CHAPTER 4: USING THE IEEE 1394-BASE
Page 93 and 94: Bytes 0-3 Bytes 4-7 Bytes 8-11 Byte
Page 95 and 96: Bytes 0-3 Bytes 4-7 Bytes 8-11 The
Page 97 and 98: Bytes 0-3 Bytes 4-7 Bytes 8-11 Byte
Page 99 and 100: Read and clear latches for individu
Page 101 and 102: Scaling CHAPTER 4: USING THE IEEE 1
Page 103 and 104: Read and Write Packet Structure Par
Page 105 and 106: CHAPTER 4: USING THE IEEE 1394-BASE
Page 107: CHAPTER 4: USING THE IEEE 1394-BASE
Page 111 and 112: CHAPTER 5: ADVANCED MODBUS PROGRAMM
Page 113 and 114: APPENDIX A Appendix A SNAP Ethernet
Page 115 and 116: Status Area Read—Read Only This i
Page 117 and 118: Date and Time Configuration—Read/
Page 119 and 120: Security Configuration—Read/Write
Page 121 and 122: Serial Module Configuration—Read/
Page 123 and 124: Wiegand Serial Module Configuration
Page 125 and 126: SNMP Configuration—Read/Write (Do
Page 127 and 128: Starting Address Length Type Descri
Page 131 and 132: Digital Point Read—Read Only NOTE
Page 133 and 134: Analog Point Read—Read Only See
Page 135 and 136: Analog and Digital Point Configurat
Page 137 and 138: Digital Events and Reactions—Read
Page 141 and 142: Analog Point Calculation and Set—
Page 143 and 144: Analog Read and Clear/Restart—Rea
Page 149 and 150: Serial Event Configuration—Read/W
Page 157 and 158: Data Log—Read/Write (Does not app
Page 159 and 160:
Appendix B Table of Offsets Introdu
Page 161 and 162:
Module Point (Decimal) Point (Hex)
Page 163 and 164:
Index A access, setting up SNMP sec
Page 165 and 166:
error codes IEEE 1394-based protoco
Page 167 and 168:
O off-latch, 20 offset, 24 IEEE 139
show all

snap ethernet-based i/o units protocols and programming guide

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?