Texas Instruments 990 Operation Manual page 258

~~------------------
~
945255-9701
and beginning PROM/ROM bit address of string
3
BRBA = RWW . BCA +
~
(DRi + CRi . 1Ri)
i=l
This algorithm may be expressed in FORTRAN in two different ways. The first encodes the
algori thm directly.
C
C
C
IMPLICIT INTEGER (A-Z)
N
=
MM 1
*
MM2
*
MM3
GENERATE ALL BEGINNING BIT ADDRESSES
DO 10 KK
=
I,N
K = KK-l
CMI = MOD (K,MMl)
CM2 = K/MMl
CM3
=
K/MMI
*
MM2)
BMBA
=
8
*
BMA + DMI + CMl
*
IMl + DM2 + CM2
*
1M2 + DM3 + CM3
*
1M3
10
CONTINUE
The second method utilizes nested DO-loops to avoid the calculations of CM 1, CM2, and CM3.
IMPLICIT INTEGER (A-Z)
C
C GENERATE ALL BEGINNING BIT ADDRESSES
C
DO 30
I
=
l, MM3
CM3
=
1-1
DO 20 J = 1, MM2
CM2 = J - 1
DO 10 L-l,MMl
CMl=L-l
BMBA
=
8
*
BMA + DM 1 + CM 1
*
1M 1 + DM2 + CM2
*
1M2 + DM3
+CM3
*
1M3
10 CONTINUE
20 CONTINUE
30 CONTINUE
A similar mechanism would generate all beginning ROM bit addresses.
F-2
Digital Systems Division .