Why aren't assembler language programs discussed under interlanguage communication in Language Environment manuals or in IBM presentations?
Assembler language is not considered a separate language by Language Environment. There is no runtime library associated with assembler programs, so there are no runtime conflicts with assemblers and other High-Level Languages (HLLs). Assembler programs can call and be called by any of the HLLs supported by Language Environment.
Can OS/VS COBOL or VS COBOL II programs call Language Environment-conforming assembler programs?
For a complete list of calls between COBOL and assembler (including whether they are supported or not when running under Language Environment), see Runtime support for assembler COBOL calls on non-CICS and Runtime support for assembler COBOL calls on CICS.