IBM 1130 User Manual page 124

Section
Subsections Page
20
30
I
20 01
Card Design Principles
Determining Card Data
The first step in card design requires a study
of the final report that is to be printed from the
card and a listing of data needed for it. Next the
procedure is studied, and any data needed for proc-
essing but not for the report is added to the same
listing. Every item is recorded on a worksheet.
Provision must be made for recording in the card
all data that is listed, unless it is calculated or
otherwise generated.
A check should be made that the necessary
reference data is included. Reference data should
be sufficient to:
1. Identify the transaction with the original
source document from which it was created.
2. Indicate the date on which the transaction
occurred.
3. Establish some reference, such as invoice
number, batch number, account number, or
salesman number.
Care should be taken to avoid duplicate or un-
necessary reference data.
Determining Field Size
The number of pOSitions required to record each
type of information should be determined.
The size of the field for card codes, invoice
number, and account number is determined by the
largest single number to be recorded. With
quantity and amount fields, the largest amount
that will occur on a reasonably frequent basis must
be determined, rather than the largest it could
ever be. If the largest possible amount is lmown
and its chances of occurring are rare, multiple
cards may be punched for the transaction.
After all card data is listed, the number of
columns required should be added. If this is
between 80 and 100, it may be possible to reduce
it to 80. If it is over 100, an additional card is
evidently required. At this point a check should
be made to see whether the fields can be rear-
ranged so that all transactions need not have
multiple cards, but could have if necessary.
Master information can be punched in one card and
variable information in the other. Sufficient refer-
ence information must be included in the second
card if sorting is required.
Some techniques to be considered for reducing
the number of card columns are:
• Reduce the size of reference fields by repeat-
ing the numbering series more frequently. For ex-
ample, invoice number may start with 1 each quar-
ter instead of each year.
• Record in the eleventh and twelfth punching
positions various codes that may be using a sepa-
rate punching position.
• Avoid unnecessary data: for example, the use
of both an order number and an invoice number may
not be necessary if one will provide adequate ref-
erence to the other.
• Reduce the size of reference fields by recod-
ing.
It
may be possible to eliminate several posi-
tions.
• Reduce the number of columns required for
recording reference data by ignoring positions that
are not essential for this purpose.
If more than one card is to be used to hold a
"record", the division of information between the
cards can be made on the following bases:
1. Place constant information in one card
(master) and temporary information in the second
card (detail).
2. If more than one source document is used,
place the information of each document on a sepa-
rate card and code the cards.
3. When one transaction affects two different
accounts, design a card for each account with
differing degrees of detail as required by each
account.
4. For printing a bill, order, or other notice,
design a card for each section of the form. Some
of these cards (for example, name and address
cards, constant data cards) can be reused.
Determining the Sequence of Fields
Four basic factors are involved in determining
field sequence:
1. Sequence of data on the source document
from which the new card will be punched
2. Machines and programs used to process the
new cards
3. Manual operations in which the new card will
be used
4. Location of identical data in other cards with
which the new one will be processed
Keeping the sequence of fields similar to the
order in which the data is read from the source
document will make the keypunching operation
faster and more accurate. This is especially
important since keypunching is a manual operation
and therfore subject to far greater fluctuation in