QD061             0                    1                     2                     3                     4                     5                     6                     7                     8                     9

                         The CCW addr fetch and update routine is used only during         this CCW is to be skipped and the next CCW executed. In
                         chaining. It fetches the CCW addr from local storage,             this case, eight must be added to the CCW addr to get the
A                        updates it and restores it for future chaining. Normally          addr of the CCW which is to be executed and an additional
                         the CCW addr as fetched is the addr of the CCW. Eight is          eight to get the next CCW addr.
                         added to it and stored as the next CCW addr. There is one
                         exception, and that is while doing a CC. If a Device End
                         with a status modifier is received from the control unit,

B

                              00 014 093C           00 014 0940           01 014 0941           00 014 0944           01 014 0945           01 014 094D    
                          K 0111,0      |       K 1000        |       K 1000        |       K 0110,1      |       |             |       |             |    
                          A 0>S         |       A R+KL>RC     |       A R-KL+1>V    |       A GT>Z        |       A R+0+1>R     |       A R-0>U       |    
C   QD091.JGE------------*S *8F      LS S*------|             |*------S WRITE       |*--O---S *8E      LS S*--O---|             |*------S WRITE       |*O------------------------------------------------------------------------------QD051------CFE
    (00)                  C 1>S0        |       C HZ>S4       |       C ANSNZ>S2    |   |   C LZ>S5       |   |   |             |       C ANSNZ>S2    | |                                                                              (10)
    Selr Ch               |          014V   ----|          014V       |          014V --+---|          014V   |   |          014V       |          014V |                                                                              Selr Ch CD
    CCW addr              R 0,0       40R   |   R 0,1       41R       R S0,0      44R | |   R AC,1      45R   |   R 0,1       4DR       R S0,S5     08R |                                                                              CCW fetch
    fetch CD              C1--    00 --CA   |   C2--    01 --CB       C3--    *0 --CC | |   C4--    *1 --CD   |   C5--    01 --CE       C6--    ** --CF |  
    waiting                                 |  Low CCW addr+8                         | |  CC=test Op In      |  High CCW addr                          |  
D                                           |                                         | |                     |                                         |  
                                            |                                         | |                     |                                         |  
                              00 014 093E   |       10 014 0942           11 014 0943 | |       10 014 0946   |       11 014 0947           11 014 094F |         01 014 0909           11 014 0937    
                          K 0111,0      |   |   K 0001        |       K 1000        | | |   K 0110,1      |   |   |             |       |             | |     K 0101,1      |       K 1100,0      |    
                          |             |   |   A R+KH>RC     |       A R-KL+1>V    | | |   |             |   |   A R+0+C>RC    |       A R>U         | |     |             |       |             |    
E   QD091.JJE---------O--*S *8F      LS S*--O---|             |*------S WRITE       |*- ----S *8E      LS S---O---|             |*------S WRITE       |-O-----S *8D      LS S*------S WRITE    GR S*-----------------------------------QD051------EHE
    (10)              |   C 0>S2        |       |             |       C HZ>S4       |       |             |       |             |       C ANSNZ>S2    | |     |             |       C K>GA        |                                    Selr Ch CC
    QD111.EHE----------   |          014V       |          014V       |          014V       |          014V       |          014V       |          014V | ----|          014V       |          014V                                    CCW fetch
    (10)                  R S1,0      40R       R 1,1       43R       R 0,0       44R       R AC,1      45R       R 1,1       4FR       R S0,S5     08R | |   R 1,1       37R       R 1,0       72R    
    Selr Ch               E1--    *0 --EA       E2--    11 --EB       E3--    00 --EC       E4--    *1 --ED       E5--    11 --EE       E6--    ** --EF | |   E7--    11 --EG       E8--    10 --EH    
    CCW addr             Fetch low             Low CCW addr+16       V=low CCW addr        CDA                   High CCW addr+        U=high CCW addr  | |  CC-Op In down         Addr Out
F   fetch                CCW addr                                    Store next low        Fetch high CCW addr   carry                 Store next high  | |
                                                                     CCW addr                                                          CCW addr         | |
                                                                                                                                       S2=0=high CCW    | |       00 014 0908    
                                                                    S2=0=low CCW addr is 00                                            addr is 00       | |   K 1111        |    
                                                                    S4=1=low CCW addr is 00 or 08                                                       | |   A GTL+K>R     |    
G                                                                                                                                                       --+---|             |*---
                                                                                                                                                          |   |             |   |
                                                                                                                                                          |   |          014V   |
                                                                                                                                                          |   R 0,0       48R   |
                                                                                                                                                          |   G7--    00 --GG   |
                                                                                                                                                          |  CC-Op In up        |
H                                                                                                                                                         |  Test Op In         |
                                                                                                                                                          |                     |
                                                                                                                                                          |       11 014 090B   |       00 014 0948    
                                                                                                                                                          |   K 1111        |   ----|             |    
                                                                                                                                                          |   A GTL+K>Z     |       A R+0+1>R     |    
J                                                                                                                                                         O---|             |*--O---|             |*---
                                                                                                                                                          |   |             |   |   |             |   |
                                                                                                                                                          |   |          014V   |   |          014V   |
                                                                                                                                                          |   R AC,0      48R   |   R AC,1      09R   |
                                                                                                                                                          |   J7--    *0 --JG   |   J8--    *1 --JH   |
                                                                                                                                                          |  Test Op In,Adr In  |                     |
K                                                                                                                                                         |  and StaIn          |                     |
                                                                                                                                                          ----------------------+----------------------
                                                                                                                                                                                |                             00 014 094C
                                                                                                                                                                                |                         K 1000        |
                                                                                                                                                                                |                         A 0+KH>R      |    
L                                                                                                                                   ---------------------------------------------                     ----|             |*-------------QD161------LJE
                                                                                                                                    |                                                                 |   C 0>S4,S5     |              (10)
                                                                                                                                    |                                                                 |   |          014V              Selr Ch
                                                                                                                                    |                                                                 |   R 1,0       2AR              Inf Ctrl Chk
                                                                                                                                    |                                                                 |   L9--    10 --LJ
                                                                                                                                    |                                                                 |  R=Cat. Num 80
M                                                                                                                                   |                                                                 |
                                                                                                                                    |                     -----------------------                     |
                                                                                                                                    |       10 014 094A   |       11 014 094B   |       01 014 0949   |       10 014 094E
                                                                                                                                    |   K 0111,0      |   |   K 1111        |   ----|             |   |   K 0110,1      |
                                                                                                                                    |   A V-KL>RC     |   |   A V-KL>RC     |       |             |   |   A V-0+C>RC    |    
N                                                                                                                                   ----S *8F      LS S*--O---|             |*------S STORE       |*--O---S *8E      LS S*---
                                                                                                                                        C 1>S0        |       |             |       C 0>S0        |       |             |   |
                                                                                                                                        |          014V       |          014V   ----|          014V       |          014V   |
                                                                                                                                        R S1,1      49R       R 0,1       49R   |   R S0,0      4CR       R 0,1       49R   |
                                                                                                                                        N6--    *1 --NF       N7--    01 --NG   |   N8--    *0 --NH       N9--    01 --NJ   |
                                                                                                                                       Time-out              Jumped             |  Store corrected       R=high CCW addr    |
P                                                                                                                                      R=low CCW addr-8      R=low CCW addr-16  |  CCW addr              1 or 0             |
                                                                                                                                                                                ---------------------------------------------
 
                         If doing CD, this routine then goes to the CCW fetch
                         routine. If doing CC, this routine checks that Op In and
Q                        Status In has dropped and then starts the Unit Selection.
                         If the interface does not clear, the CCW address must be
                         corrected and the routine then goes to the error routine
                         and indicates an Interface Control check.
 
                         S2,S4 will be used to determine if this CCW adder was
R                        obtained by a storage wrap of a 64k storage and indicate
                         a program check if storage wrap did occur. While
                         chaining, a program check is indicated when the CCW addr
                         is 0000 and also when a jump has occurred and the CCW
                         addr is 000X.
S

 Q
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 6                                                                                                                                                | 128055        02/10/66 | Mach          2030       | Date  10/12/66          Sheet    1  QD061 |
 1                                                                                                                                                | 128061        10/06/66 | Name                     | Log    2245             Version    014    |
                                                                                                                                                  |                        | Mode          Manual     |                                           |
                                                                                                                                                  |                        | P.N.          837192     |    Selr CHannel CCW addr                  |
                                                                                                                                                  |                        | IBM Corp.                |    fetch and update                       |