MIL-STD-188-174 Base Document:1990

1 SCOPE
1.1 Purpose
1.2 Scope
1.3 Application
1.4 System standards and design objectives
1.5 Tailoring
2 APPLICABLE DOCUMENTS
2.1 Government documents
2.1.1 Standards
2.2 Order of precedence
2.3 Source of documents
3 DEFINITIONS
3.1 Definition of terms
3.1.1 Bit error ratio (BER)
3.1.2 Character set
3.1.3 Data rate
3.1.4 Loop rate
3.1.5 Mode I
3.1.6 Mode II
3.1.7 Mode V
3.1.8 Mode VI
3.1.9 Mode VII
3.2 Abbreviations and acronyms
4 GENERAL REQUIREMENTS
4.1 Mode VI channel coordination procedures
4.2 Duplex operation
4.3 Characters
4.3.1 Data characters
4.3.2 Control characters
4.3.3 Framing characters
4.4 High integrity
4.5 Path delay accommodation
4.6 Octet code
5 DETAILED REQUIREMENTS
5.1 Mode VI protocol
5.2 Mode VI message block and message block groups
5.3 Message block structure
5.3.1 Normal message blocks
5.3.2 Short message blocks
5.4 Data formats
5.4.1 ASCII
5.4.2 Other data codes and binary streams
5.5 Framing characters
5.5.1 Start of header (SOH)
5.5.2 Select (SEL) character
5.5.3 Start of text (STX)
5.5.4 Block number (BN)
5.5.5 End of transmission block (ETB)
5.5.6 End of text (ETX)
5.5.7 Block parity (BP)
5.6 Special short blocks
5.6.1 End of medium (EM) block
5.6.2 Mode change (MC) block
5.6.3 Record mark (DC3) block
5.7 Message block groups
5.8 Message transmission control
5.8.1 Control character response
5.9 Traffic state
5.9.1 Transmitter
5.9.2 Receiver
5.9.3 Message block retransmission
5.9.4 Receipt of a duplicate block
5.9.5 Excessive block retransmission
5.9.6 Block framing errors
5.9.7 Excessive unexpected characters
5.10 Mode VI traffic state
5.11 Character and bit transmission
5.12 Mode VI timing and time outs
5.13 Safe message store
5.14 Mode VI through put calculation
5.14.1 Example
5.15 Tabulation transmission times
5.16 Mode VI transmission efficiency
6 NOTES
6.1 Key word listen
FIGURES
FIGURE 1 Mode VI - normal block - 1st block of message
       2 Mode VI - normal block - one block message
       3 Mode VI - normal block - text block
       4 Mode VI - normal block - last block of message
                  - text block
       5 Mode VI message block construction
       6 Mode VI - short block - 1st block of message
       7 Mode VI - short block - one block message
       8 Mode VI - short block - text block
       9 Mode VI - short block - last block of message
                  - text block
       10 Example of EM block
       11 Example of MC block beginning/end of binary
          text
       12 Example of DC3 block - end of record
       13 Mode VI message transmission
       14 Mode VI message reception
       15 Conversion of nine-track tape to Mode VI
          text characters
       16 Typical structured format for seven track
          tape
       17 Typical Mode VI transmission structured
          format actions/reactions
       18 Typical structured format for seven track
          tape
       19 Mode VI transmission structured format action
          /reaction
       20 Nonstructured format for seven track tape
       21 Mode VI transmission nonstructured format
          action/reaction
       22 Structured format for nine track tape
       23 Mode VI transmission nonstructured
          format action/reaction
       24 Nonstructured format for nine track tape
       25 Mode VI transmission nonstructured format
          action/reaction
TABLES
Table I American Standard Code for Information
          Interchange (ASCII) and Mode VI data
          characters
      II Mode VI data character control and framing
          eight bit environment character set
      III Mode VI eight bit control and framing codes
      IV Mode VI select framing characters
      V Example of Mode VI acknowledgement sequences
      VI Mode VI - reject and cancel message procedures
      VII Normal Mode VI procedures
      VIII Mode VI block framing errors
      IX Mode VI timing and time outs
      X Mode VI transmission - time in seconds
      XI Conversion from seven track tape to Mode VI
            data (block) character
APPENDIXES
Appendix A DEPARTMENT OF DEFENSE DIRECTIVE 4640.11, 21
            DECEMBER 1987 SUBJECT: MANDATORY USE OF
            MILITARY TELECOMMUNICATIONS STANDARDS IN THE
            MIL-STD-188 SERIES
Appendix B LIST OF ABBREVIATIONS AND ACRONYMS USED IN
            MIL-STD-188-174
         C DATA CONVERSION TECHNIQUES FOR SYSTEMS USING
            NONSTANDARD CODES
Paragraph 10 GENERAL
          10.1 Scope
          10.2 Application
          10.3 Application guidance
          20 APPLICABLE DOCUMENTS
          30 DEFINITIONS
          40 GENERAL REQUIREMENTS
          40.1 Minimum criteria
          40.2 User responsibility
          50 SPECIFIC METHODOLOGY
          50.1 Introduction
          50.2 Magnetic tape messages
          50.2.1 Structured format
          50.2.2 Nonstructure format
          50.2.3 Tape marks
          50.2.3.1 Record mark (DC3) block
          50.2.4 Code translation
          50.2.4.1 Seven track tape (SEL character B)
          50.2.4.2 Nine track tape (SEL character C)
          50.2.5 Transmission sequences
          50.2.5.1 Header

Ensures interoperability and to promote commonality of communications equipment and subsystems using Mode VI channel coordination procedures.