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WWAM Architecture

by Robert Weaver

Comment by M. Papo, June 2014
"Off hand, without deeper study I see nothing wrong on his interpretation."

Updated April 24, 2009
Reference WWAM LOGIC by M. Papo, 1957, 900 K bytes .pdf

Here's my try at it.

Think of WWAM as a 1401 without a program. And with an IBM 650 "address of next instruction"

Memory is organized into "groups" each group having 80 characters.

[Fig 2 lower right shows 1st 9 storage groups}

On the control panel "memory splits" (each with 3 hubs) are used to define fields. If a particular group is to have 5 fields, then 5 splits are used. The three hubs of a split are:

  1. one hub is the field pickup for an operation (ADD, for example)
  2. one hub is for linking the 5 splits together and to the particular 80 character group
  3. one hub if for the "units" position (1-80), fields extend to the units position of the next field of the fields linked together
    [Fig 2 upper right. The 1st 5 splits are linked to storage group 5, the units link to 4,10,25,?,80. Word 3 in storage group 5 then is positions 11-25.
    The next 3 storage splits are linked to storage group 8; units link to 11,28,?

Note that there could be multiple sets of memory splits, defining a different field layouts, wired to the same group. Thus the ability to handle punched cards with different formats in the same input deck.

The control panel has a sequence of program steps, each with 5 hubs.

[Fig 2 upper left]
  1. two hubs are used to select the next program step. One hub is an entry "IN", the other is an exit "OUT". Each instructions OUT is wired to another instructions IN (or END). Thus the flow of control, the OUT/IN specifying the next instruction to execute, with branching possible by using relays to to select the wiring to the IN instruction.
  2. one hub is the operation (ADD in Fig 2)
  3. one hub is to the memory split pickup of the R0 add operand [Fig 2 word 3 of group 5]
  4. and one is to the memory split pickup of the R1 add operand [Fig 2 word 3 of group 8]
(WWWAM terminology RO, RI fields)

There are more details re card reading and print line editing, but the above should make it possible to see the basic differences between the 407, WWAM, and the 1401.

dick w

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