On 11/6/19, esst...@juno.com <esst...@juno.com> wrote: > Hi,.I tried posting this at IBM-MAIN, however I am experiencing problems > with that site, so I decided to post here. > . > LA 1,1(0) > ST 1,AXNUM > . > L 4,AXVAL > ETDEF TYPE=SETDEF > . > the work areas are: > AXL DS 0F AXLIST > AXNUM DS H Number of AXs Requested > AXVAL DS H Returned AX (OR EAX) > . > The example is trying to show how to set an EAX for a SETDEF macro. > . > My understanding - the first 3 instructions want to establish an EAX.. > The first Instruction load 1 off of Register 0. > Is register 0 assumed to be zero ?
I believe Register 0, used as a base register, is defined to be zero. > It is my understanding that Register 0 cannot be used as a base register. > Register 0 can be used to address the first 4096 bytes of an address space. Yes, because when used as a base register, register 0 is defined t be zero. -- Bob Netzlof a/k/a Sweet Old Bob
