Split Register
/
As was pointed out in the preceding pages, each of the B, C, 0, E and F registers can
be split into two parts, each with a capacity of 11 digits plus decimal point and sign. The left
part of the register is identified with the lower case letter corresponding to its companion's
designation. The lower case designation is obtained by entering the corresponding upper case
letter and touching the "I" key, e.g. c = C/o The right side of the split register retains its
original upper case letter designation.
The computer has built-in self-regulating circuitry that alerts the operator with an error light if
an attempt has been made to transfer a value larger than 11 digits to a split register, or to
split a register that already contains a value greater than 11 digits.
Nevertheless. a register can be used as both a whole and a split register at varying times
throughout a program by using the clear (*) instruction before shifting from whole to split or
vice versa. For example:
In phase one of a program, register B is used as a split register (b,B); then in phase two.
register B is to be used as a whole register:
1.
At the end of phase 1, a B/* instruction frees the left side of the register so that in phase
2, it can be used in conjunction with the right side as a whole register.
2.
At the end of phase 2, a B* instruction frees the whole register so that it can be used as a
split register when the program starts again with phase 1.
- 16 –
