VM370 Rel 6 Data Areas and Control Block Logic (Mar79)
Page261(261 of 342)
BUFDSECT BOFDSECT is used to transmit buffer control information and tuffer data to and frem programmable remote stations. The buffer sent across the TP line starts at EUFSTARTi the first 7 bytes of BUFDSECT are used by the DMTSML line driver but are not transmitted. $BUFPOOL in DMTSML points to a queue of available TP buffers; $INBOF in module DMTSML peints to a queue of TP buffers that have been received from a remote station and are waiting to be deblocked. $OUTBUF in DMTSML points to a queue of TP buffers that are ready for transmission to remote stations. Hexadecimal Displacement o o 4 6 7 9 A C o 4 8 C r---------------------------------------------------------, BUFCOUNT BUFSTART Field Name BUFBEGIN DS BOFCHAIN DC BUFCOUNT DS BUFSTAT DS BUFFAKE EQU BUFRESP EQU BUFNAK EQU BUFTEXT BQU BUFOCHEK EQU BUFSTART DS BUFBCB DS BUFFCS DS BUFDATA DS BUFBCB OF A (0) 1H 1C in BUFSTAT i'01'----- X'02' v,nll' A·V .... X'08' X'10' CL2 1C CL2 OF BUFCBAIN BUFSTAT BUFSTART EOFFCS BUFDATA Field Descriptien, Contents, Meaning Beginning of the buffer Buffer chain field count of bytes to transEit Buffer status byte Dummy buffer indicator Response only in buffer NlK response being sent Buffer contains text information Unit check expected Bisynchronous transmission control bytes Block control byte Function control sequence Data portion of TP buffer Section 3. RSCS tata Areas and Contrel Blocks 249
COMDSECT COMDSECT defines address constants used as pointers to subroutines co.mon to all RSCS modules. These subroutines are contained in module DMTCOM. COMDSECT is Fointed to by TCOM in SVECTORS. 0 4 8 C 10 14 Hexadecimal Field Displacement Na.e o 4 8 C 10 14 GLINKREQ GPAGEREQ FPAGEREQ PMSGREQ GMSGREQ GTODEBCD DS 1A DS 1A DS 1A DS 1A DS 1A DS 1A , GLINKREQ GPAGEREQ FPAGEREQ PMSGREQ GMSGREQ GTODEBCD Field Description, Contents, Meaning Get link tatle entry routine Get Fage of main storage Free page of main storage Put .essage element into message stack Re.ove message ele.ent fro. .essage stack convert S/370 TOD to EBCDIC 250 IBM VM/370 Data Areas and Control Block Logic