Read-Out, Punch-Out - IBM 29 Instruction Manual

Transfer information from registers BA, 7 A, 6A, and
SA to BB, 7B, 6B, and SB.
Retain information in registers BB, 7B, 6B, and SB.
S. Cycle 5 ( store an B) :
Close numeric-B latch contact.
Enter numeric information into register BA and
energize the punch clutch.
Read-out, Punch-out
• Read out the stored information.
• Set up the interposer magnets.
• Energize the escape and punch clutch magnets.
• Punch the information into the card.
Description
The punch-out of a left-zero field is like an auto-dupli-
cation operation. It is necessary to take a punch cycle
without an escapement to start the punch-out. During
the time that P5 is made, the information in the first
register is read into the interposers. Information in the
interposers causes the first escapement and the next
punch cycle.
It is necessary to prevent the transfer of information
stored in the register for the first cycle (dummy cycle)
to allow the first register to be read and cleared. As
each column is punched, the information is transferred
from register to register. This is done so the informa-
tion to be punched is in register IA at P5 time of each
punch cycle. The information is stored in BCD and
must be converted to decimal form before reaching
the interposer magnets. This is accomplished by using
register IA relays to form a decode tree.
Read-out, Punch-out Cycle 1: Refer to Figure I-B
for timing within cycles. The operator presses the left-
zero key, closing the left-zero latch contact. This ener-
gizes the read-out relay ( 326) and the punch clutch.
The left-zero field I, 2, and 3 relays ( 3I5, 324, 305)
and key-entry relay ( 304) are being held by starwheel
2. The P-cam-gate relay ( 309) is up, being picked at
I75° of the last cycle by P4. We would normally trans-
1-8
Transfer registers BB, 7B, 6B, and 5B to 7 A, 6A, SA,
and 4A.
Restore the keyboard.
Transfer information from registers BA, 7 A, 6B, SB,
and4B.
Retain information in registers BB, 7B, 6B, SB,
and 4B.
fer information from the B registers to the A registers
at 10° when P3 makes, but for this cycle we prevent
the P3 pulse from going to the registers. This is done
with the N/c 3-point of the read-out relay (326).
Because we do not transfer the information, we must
hold the information in the register for this first cycle.
This is accomplished by using the
N /
o 5-point of the
read-out relay ( 326) and starwheel 2. By the time that
an escapement has occurred and starwheel 2 opens, P2
is made, providing a hold to the B registers. ·when the
2-starwheel opens, the key-entry relay ( 304) and the
field I, 2, 3 relays ( 3I5, 324, 325) are de-energized.
The IA register is held during the first cycle by the
N/c
4-point of the punch-out relay ( 3I7) until
B6°
when relay 3I 7 is picked. Relay 3I 7 is picked by P5
through the N/o 2-point of the read-out relay ( 326).
Before relay 3I 7 is picked, P6 makes, providing a hold
until I50° for register IA. If the relays of register IA
were dropped at I50°, the interposer magnets circuit
would be opened by relay points.
P7 provides a continuing hold to register IA relays
until 10° of the next cycle. At PS time ( 86° to 166° )
the interposer magnets are energized through the N/o
6-point of the read-out relay ( 326) and the decode
tree of register IA relay points. It is this circuit that