Xerox WORKCENTRE 7120 User manual

Xerox Card Readers
Models712017121/712217140
Reference Manual

Code
(Hexadecimal)
02
06
12
16
32
36
OA
OE
lA
IE
3A
3E
CARD READER ORDER CODES
Function
Read Binary
Read
Automatic
Read Binary
Read
Automatic
Read Binary
Read Automatic
Read Binary
Read Automatic
Read Binary
Read
Automatic
Read Binary
Read
Automatic
Model 7120
Normal stacker
Normal stacker
AI ternate stacker
Alternate stacker
Stacki ng Action t
A
Iternate stacker 2
Alternate stacker 2
If no data overrun occurs, stack
card in normal stacker; if data
overrun occurs, stack card in
alternate stacker 2.
If neither data overrun nor
validity error occurs, stack
card in normal stacker; if data
overrun or validity error occurs,
stack card in 01 ternate stacker 2.
If no data overrun occurs, stack
card in alternate stacker 1; if
data overrun occurs, stack card
in alternate stacker 2.
If neither data overrun nor
val idity error occurs, stack
card ina I ternate stacker 1; if
data overrun or validity error
occurs, stack card in alternate
stacker 2.
Alternate stacker 2
AI ternate stacker 2
Model 7140
Normal stacker
Normal stacker
AI ternate stacker
AI ternate stacker
Normal stacker
Normal stacker
If neither data overrun nor read
verify error occurs, stack card
in normal stacker; if error occurs,
stack card in alternate stacker.
If neither data overrun, validity,
nor read verify error occurs,
occurs,
stack card in normal
stacker; if data overrun, validity,
or read verify error occurs, stack
card in alternate stacker.
Al1 ternate stacker
AI ternate stacker
Same as 'OA'
Same as 'OE'
t Models 712117122 accept all the above order codes but offer no alternative stacki ng si nce they have one stacker.
;.

Xerox Corporation
~, 701 South Aviation Boulevard
EI Segundo, California 90245
213 679-4511
Xerox Card Readers
Models 7120/7121/7122/7140
Reference Manual
90 09 70E
November 1970
Price: $1.00
XEROX
Printed in U.S.A.

ii
REVISION
This publication, 9009 70E, is a revision of the Xerox Sigma Card Readers Reference Manual, 9009 70D (dated
May, 1970). A change in text
from that in the previous manual is indicated by a vertical line in the margin of the
affected page.
RELATED PUBLICATIONS
Title
Xerox 530 Computer/Reference Manual
Xerox Sigma 2 Computer/Reference Manual
Xerox Sigma 3 Computer/Reference Manual
Xerox Sigma 5 Computer/Reference Manual
Xerox Sigma 6 Computer/Reference
Manual.
Xerox Sigma 7 Computer/Reference Manual
Xerox Sigma 8 Computer/Reference Manual
Xerox Sigma 9 Computer/Reference Manual
Xerox Meta-Symbol/LN, 0
PS Reference ManuaI (S igma 5-9)
Xerox Symbol/LN, OPS Reference Manual (Sigma 5-9)
Xerox Macro-Symbol/LN,OPS Reference Manual (Sigma
5-9)
Xerox Symbol/LN,OPS Reference Manual (Xerox 530 and Sigma 2/3)
Xerox Extended Symbol/LN,OPS Reference ManuaI (Xerox 530 and Sigma 2/3)
Publ ication No.
90 1960
900964
90 1592
900959
901713
900950
90 1749
90 1733
900952
90 1790
90 1578
90 1051
901052
Manual Content Codes: BP -batch processing, LN -language, OPS -operations, RBP -remote batch processing,
RT - real-time, SM -system management, TS -time-sharing, UT -utilities.
ALL SPECIFICATIONS SUBJECT TO CHANGE WITHOUT NOTICE
~"

CONTENTS
~,
1. GENERAL DESCRIPTION
Card File Unloading Procedure
(Models 7121/7122) 19
Introduction
Reader Ha I ted
19
Reader Running 19
2.
FUNCTIONAL DESCRIPTION 2
Card File Loading Procedure (Model 7140) 19
Reader Halted
19
Data Representation
2 Reader Running 19
EBCDIC Card Format
2
Card File Unloading Procedure (Model 7140) __ 19
Binary Card Format 2 Reader
Halted
19
Card Reader States
3 Reader
Runn ing 19
Operational States
3
Conditions
3
APPENDIXES
Modes 3
Transi tions Between States
3
A.
XEROX EBCDIC CARD CODES 20
Data Transfer 3
B.
PROGRAMMING EXAMPLES 22
3. PROGRAM INTERFACE 5 Sigma
5-9 Programming Example 22
Read Orders 5
Xerox 530 and Sigma 2/3 Programming Example_ 23
Read Card Binary 5
Read Card Automatic 6
ILLUSTRATIONS
Key Events 6
Start Input/Output
6
Model 7120 Card Reader, Model 7140 Card
Unusual End
Conditions
6 Reader, Model 7121/7122 Card Reader iv
Channel End CondiHons
6
Error Conditions
7 1. EBCDIC Read
Operation
2
Incorrect Length 7
2.
Binary Read Operation
2
Invalid EBCDIC Punches 7
Data Overrun
7 3. Controll ing
System/Card Reader Actions
11
Read Verify (Model 7140-02) 7
4.
Card Reader Event Times (Model 7120) 12
Not Operational Conditions
7
Card Reader Status Response 7
5.
Card Reader Event Times (Model 7121)
13
I/O Instruction Status Bits 7
6.
Card Reader Event Times (Model 7122) 14
Device Status Byte 7
Operational Status Byte 9
7.
Card Reader Event Times (Model 7140)
15
Programming Considerations
9
8.
Model 7120 Card Reader Control Panel
16
Sequence of Activity
9
Timing Information 9
9.
Models 7121/7122 Card Reader Control Panel
__ 16
10.
Model 7140 Card Reader Control Panel
17
4.
OPERA liONS
16
11.
Model 7120 Input Hopper
18
Introduction
16
12.
Model 7120 Mul tiple Output Stackers
18
Operator Controls (Model 7120)
16
OPER'L/POWER
16
13.
Models 7121/7122 Input Hopper and Output
START
16
Stacker
18
FAULTjRESET
16
14.
Model 7140 Input Hopper and Output Stackers __ 19
STOP
16
Operator Controls (Models 7121/7122/7140)_- 16
TABLES
POWER
16
START
16
STOP 17 1.
Characteristics
1
FEED/READ 17
2.
Card Reader State Transitions 4
RESET
17
3.
Binary Mode Stacking Action
5
HOPPER/STACKER 17
4.
Automatic Mode Stacking Action
6
-~,
Card File Loading Procedure (Model 7120) 17 5.
Card Reader I/O Instruction Execu'Hon Response_
8
Card File Unloading Procedure (Model 7120) __ 18
6.
Device Status Response for SIO, TIO, and HIO_
9
Card File Loading Procedure (Models 7121/7122)_ 18
7.
Device Status Response for TDY
9
Reader Halted
18
8.
Devi ce Status Response for AIO
10
Reader Runn ing
18
9.
Operational Status Byte 10
iii

Model 7120 Card Reader
Model 7140 Card Reader
Model 712117122 Card Reader
iv

1. GENERAL DESCRIPTION
INTRODUCTION
Xerox Models 7120/7121/7122/7140 Card Readers are
capable of reading standard 80-'column tabulating cards
conforming to the Electronic Industries Association (EIA)
punched card standard RS-292.
Cards
are read serially, column by column, in either of
two
read modes: binary (absolute) or automatic (EBCDIC).
Automatic read mode switching, from
EBCDIC to binary,
facilitates reading of intermixed EBCDIC- and binary-
punched cards.
The
photoelectric read station reads each 12-bit column of
an 80-column card. The data thus sensed are presented to
the controlling system as a series
of 8-bit bytes.
Transport
check and read check faci Iities provide for detec-
tion of "not operational" conditions by the controlling sys-
tem. Empty input hopper and full output
stacker conditions
are also signaled to the controlling system.
Table 1. Characteristics
Operati ng Characteristi cs
Model 7120 Models 7121/7122 Model 7140
Readi ng speed 400 cards/minute 400 cards/minute (7122) 1500 cards/minute
200 cards/minute (7121)
Hopper
capacity 1200 cards 1200 cards 2500 cards
Stacker capacity
1000 cards/stacker
1000 cards 2000
cards/stacker
Number of stackers 3 1 2
Physical Dimensions
Height
24 in.
17 in.
40 in.
Width 32 in.
21 in.
37.5 in.
Depth 25
in.
31.5 in. 33
in.
Weight (approximately)
450 Ib
200lb
350lb
Recommended access area
3 ft on all sides 3 ft on
all sides 3 ft on
all sides
Environmental Characteristics
Power Requirements 120
vac,
120 vac, 120
vac,
60 Hz, si ng Ie-phase,
60 Hz, single-phase
60 Hz, single-phase,
2 amps 8 amps
16 amps
Operati ng temperature
60
0F to 900F
60
0F
to 900F
60°F to 900F
Operating humidity (relative) 25% to 80% 25% to
80%
25% to 80%
General Description

2. FUNCTIONAL DESCRIPTION
DATA REPRESENTATION
A single 80-column card can contain data in either of two
formats: EBCDIC
or binary.
EBCDIC CARD FORMAT
In the EBCDIC card format there are 256 valid punch con-
figurations for a single card column (see Appendix A), each
of which is translated into an 8-bit code in the range 0-
2551Q(0016-FF16). Thus, the EBCDIC card image (i.e.,
the 80 columns of punch configurations) consists of a trans-
lated string of 8-bit bytes, with the first byte of the string
corresponding to the configuration punched in column 1 and
the last byte of the translated string corresponding to col-
umn 80 •. The card image is always presented to the control-
ling system in column order.
Figure 1 illustrates how the first two columns of an EBCDIC
card image are presented to the controlling system. Note
that column 2 contains an invalid EBCDIC punch configura-
tion, which is translated as 8 zeros and which causes a trans-
mission data error condition (see IErrorConditions" in Chapter
3). If column 1 of a card contains punches in rows 1 and 2,
the entire card is interpreted as a binary card image rather
than an EBCDIC image (see IlRead Orders" in Chapter 3).
II
)
000000000
1 2 3 4 5 6 1 8 tl
1111111111\
2122222222
3333333333
444444444
555555555
6666666~6
177171717
8888888888
Column
9999999999 J
123.; 5 6 1 B 910
~'
I
n
n+1
Byte , " , ,
Data 11100 0001 1,0000 0000 I
Bit Position 0 1 2 314 5 6 710 1 2 3 i4 5 6 7
Validity
Valid
Invalid
Figure 1. EBCDIC Read Operation
2 Functional Description
BINARY CARD FORMAT
In the binary card format there are 4096 possible punch con-
figurations for a single card column, and all configurations
are valid. In this format each card column corresponds toa
12-bit code in the range 0-4095 (00016-FFF16)' with each
row punch corresponding to a 1 in the 12-bit code. Thus,
the binarycard image consists of a string of 80 12-bitcodes,
with the first code corresponding to the actual punch con-
figuration in column 1 and the last code corresponding to
the actual punch configuration in column 80. Because
Sigma I/o systems use an 8-bit byte as the basic data group-
ing, the 80 12-bit codes are presented to the controlling
system as 120 8-b it bytes.
Figure 2 illustrates how the first two columns of a binary card
image are presented to the controlling system. Note that
for odd-numbered columns, the data in rows 12 through 5
comprise one
byte and that the data in rows 6 through 9 are
combined with the data in rows 12 through 1 of the next
even-numbered column to form a second byte. A third byte
is formed from the data in rows 2 through 9 of the even-
numbered column. Thus, for each odd- even-numbered
pair of binary card columns, the controlling system receives
a sequence of three 8-b it bytes.
Card Row
IF
12 11
o 1 2 3 4 5.6
7 8 9 12 11 j 0
112
\ I I
"-
I
...
I
Column I
Byte n
n+1
__ """'. ___ ,I r""-- ... ·---, If
I
0000000
12 J 4 567
1111111
2122222.
13333333,
414444444
155555555
61666666l
717777777
818888888
999999999
1 2 1 ~ 5 6 1 B ~
3.!56789
...
2
n+2
*
I
D.a ta.. 10 1 0 1 0 10 110 0 00 00 00 11 0 1 0 1 0 10 I
Bit P os I tI on 0 I 2 3 4 5 6 7 0 I 2 3 4 5 6 7 0 I 2 3 I 4 5 6 7
Figure 2. Binary Read Operation
The binary card image is always presented to the controlling
system in column order and in the byte sequence described
above.

CARD READER STATES
The initial state of the card reader depends on its power
status. The complete absence of power to the card reader
subsystem (that is, the absence of its prime ac power and
system
dc power) effectively removes the card reader from
the controlIing system. All attempts to access the card
reader result in a response of "no input/output address rec-
ognition" to the I/O inshuctions. Furthermore, unpredictable
status conditions are supplied if status response is requested
by
the I/O instruction. In the absence of ac power, the
presence of system
dc power will enable address recognition,
but the card reader assumes a "not operational" state. L ike-
wise, failure of power supplies internal to the card reader
causes the card reader to assume a "not operational" state.
OPERATIONAL STATES
The presence of ac and dc power, with no read station faul t
or transport mechanism fault, enables the card reader to as-
sume either of two device conditions ("ready" or "busy")
and either of two modes ("manual" or "automatic"). A read
station fault exists if one or more of the photoelectric
channels for sensing punches in the card rows have failed to
pass
the read station test in the previous card read operation.
A transport mechan ism faul t exists if a card jam exists in any
portion of the card transport area.
The exact condition and mode status of the card reader at
any given time is returned to the controlling system in re-
sponse to such I/O instructions as SIO, HIO, and no.
Other I/O instructions, such as AIO and TDV, provide more
specifi c indications of the card reader's status (see "Status
Response" in
Chapter 3). Abriefexplanationofthepossible
conditions and modes of the card reader follows.
CONDITIONS
Ready. In the" ready" condition the card reader is capable
of accepting an SIO instruction, providing no device inter-
rupt is pending. In order to be in the "ready" condition,
the card reader must be operational (that is, all conditions
defined under "Operational States" must be satisfied) and
the execution of an order to read a card is not in progress
or
pending.
Busy. In this condition the card reader has accepted an SIO
instruction. The unit will not accept a new S10 until the
current order list is completed and no device interrupt is
pending.
MODES
Manual. The card reader assumes the "manual" mode when
any condition arises requiring operator intervention before
the reader can function normally (e.g., stacker full, hop-
per empty, etc.). The "manual" mode is forced by the
operator pressing the STOP switch or RESET switch on
the card reader control panel. The reader can accept an
SIO instruction in this mode, but will not act on it in any
way until it enters the "automatic" mode.
Automatic. When all necessary conditions for successful
card
reader operation are present, the reader is placed in
the "automatic" mode by the operator pressing the START
switch on the card reader control panel (thus illuminating
the switch).
TRANSITION BETWEEN STATES
The allowable card reader state transitions and the condi-
tions causing the reader to change from one state to another
are summarized in Table 2.
DATA TRANSFER
A card read operation is initiated by the controlling system
with a
START INPUT/OUTPUT (SIO) instruction if all the
following conditions are satisfied:
1. Input/output address recognition exists.
2. The card
reader is in the" ready" condition.
3. No interrupt is pending.
If the card reader is in the "automatic" mode, it then requests
an order from the controll i ng system. After accepting a read
order, the card reader advances a card from the input hop-
per to the read station, and commences to read the card,
column by column, beginning with column 1. If reading is
performed in the EBCDIC mode, one 8-bitbyte is transmitted
to
the controlIing system for each col umn read, and a code
validity check is performed on each byte. In the binary
read mode three 8-bit bytes are transmitted to the control Iing
system for
each odd-even-numbered pai r of col umns (no
val
idity check is performed in this mode). Reading continues
until
one of the following conditions occurs:
1. The end
of the card is detected.
2. The card reader receives a "count done" or "halt" sig-
nal from the controlling system.
3. A "fault" condition is encountered.
If the card read operation was not terminated by a card jam,
the card is then routed to the stacker station, where it is
sensed and directed to the normal stacker unless:
1. The Read Automatic order specified error stacking and
the
validity check (for EBCDIC mode only) indicated
that the card contained an invalid EBCDIC punch con-
figuration, in which case the card is directed to alter-
nate stacker 2 (Model 7120) or to the alternate stacker
(Model 7140).
2. The Read order specified error stacking and a data over-
run has occurred, in which case the card is directed to
al
ternate stacker 2(Model 7120) or the alternate stacker
(Model 7140) and the controlling system is notified of
the error with the Data
Overrun and Unusual End
indicators.
Card Reader States/Data Transfer 3

3. The Read order specified error stacking and a read
verify error (Model 7140-02) has occurred, in which
case the card is directed to the alternate stacker and
the con~rolling system is notified of the error with the
read verify error indicator.
4. The Read order selected an alternate stacker uncondi-
tionally for this card, in which case the card is directed
to the selected stacker.
t
tFor Model 7120,
alternate stacker 1 or 2; for Model 7140,
a I ternate stacker or normaI stacker.
The photoelectric circuitry is automatically checked at the
beginning
of each card read cycle. If this check indicates
a malfunction, the card reader switches to the "not opera-
tional" state, lights the FAULT (Model 7120) or READ
(Models 7121/7122/7140) indicator, and signals "unusual
end" to the
controlling system.
If no "fault" or other condition caused the card reader to
switch to
the "not operational" state or the "manual" mode,
the card
reader either returns to the "ready" conditionor(if
command chaining has been specified by the controlling
system) requests a new Read order to read the next card.
Note that each read card cycle requires a Read order.
Table 2. Card Reader State Transitions
~
Present State
Ready Manual
Busy Manual Ready
Automatic Busy Automatic
Not Operational
Operational
Not possible
Not possible Not possibl e
Ready Manual
SIO accepted
ST ART switch operated
Not possible
---
with no operator inter-
vention required
Busy Manual • HIO
received
Not possible ST ART switch operated
• RESET switch operated
---
with no operator inter-
• I/O reset
vention required
• Invalid order
Ready Automatic
STOP or RESET switch
Not possible SIO
accepted
operated
---
Busy Automatic
• STOP switch operated
STOP switch operated
• Operation completed
• RESET switch operated
and card cycle com- and no operator inter-
• Execution completed
pleted but order pend-
vention required
---
and no order pending ing, or operator inter-
• HIO received
and operator inter-
vention required •
I/O reset
vention required • Inval id order
4 Data Transfer

3. PROGRAM INTERFACE
READ ORDERS
The 8-bit Read order specifies the read mode (binary or
automatic) and the stackerinwhichthecard will be stacked
upon completion of the read operation. The specified read
mode
applies to the entire card image-columns 1 through
80. Read modes may not be changed after the first col-
umn of a given card has been read. A change to binary
read mode occurs
automatically if the automatic read mode
is specified and column 1 contains punches in rows 1
and 2.
Each val id order received by the card reader causes one
card to be fed. Order modifiers may be included in the
basic Read order to specify bi nary or automatic read mode,
stack on error condition and/or selection of multiple
stackers.
Stacker select options apply to the current card being read.
The card will be directed to the specified stacker unless an
invalid EBCDIC punch configuration is encountered, a data
overrun occurs, or a read verify error (Model 7140) occurs
and the.
optional stack on error modifier bit of the Read
order is set to 1, in which case the card will be stacked in
alternate stacker 2 (Model 7120) or in the alternate stacker
(Model 7140).
The following illustration indicates the required and op-
tional bit configurations of the Read order. (Bits 0, I,
6, and 7 must be coded as shown; bits 2-5 are optional
modifier bits.)
o 2 3 4 5 6 7
00MMMM10
'----'" ...........-
I LRead
~{O Binary
1
Automatic (EBCDIC)
o Stack in stacker specified
by bits 2-3
If no error occurs, stack in
stacker specified by bits
2-3; if error occurs, stack
in alternate stacker 2
(Model 7120) or al
ternate
stacker (Model 7140)
o Stack in normal stacker
1 Stack in alternate stacker 1
(Model 7120) or
alternate
stacker (Model 7140)
3 Stack in a I ternate stacker 2
(Model 7120) or normal
stacker (Model 7140)
READ CARD BINARY
The orders (hexadecimal code) listed in Table 3 cause the
card reader to feed and read a card in the binary mode,
with the card being directed to one ofthe multiple stackers.
In the binary read mode, 120 bytes are present on a card.
Incorrect length will be signaled to the controlling system
if ei ther fewer or more than 120 bytes are requested for a
binary read card operation.
Table 3. Binary Mode Stacking Action
Order
Stacking Action
t
Model 7120 Model 7140
X'02'
Stack card in normal stacker. Stack card in normal stacker.
X'12'
Stack card in alternate stacker 1. Stack card in alternate stacker.
X'32' Stack card in alternate stacker 2.
Stack card in normal stacker.
X'OA'
If no data overrun occurs, stack card in If neither data overrun nor read verify error
normal
stacker; if data overrun occurs, occurs, stack card in normal stacker; if data
stack card in alternate stacker 2. error occurs, stack card in alternate stacker.
X'IA'
If no data overrun occurs, stack card in Stack card in 01 ternate stacker.
alternate stacker 1; if data overrun occurs,
stack card in alternate stacker 2.
X'3A'
Stack card in alternate stacker 2.
Same as 'OA'.
tModels 7121 and 7122 accept all the above order codes but offer no alternative stacking since they have
only one stacker.
Program Interface 5

Table 4. Automatic Mode Stacking Action
Order
Stacking Action
t
X'06'
X'16'
X'36'
X'OE'
X'lE'
X'3E'
Model 7120
Stack card in normal stacker.
Stack card in alternate stacker 1.
Stack card in alternate stacker 2.
If no validity error or data overrun occurs,
stack card in normal stacker; if validity
error or data overrun occurs, stack card in
alternate stacker 2.
If no validity error or data overrun occurs,
stack card in alternate stacker 1; if validity
error or data overrun occurs, stack card in
alternate stacker 2.
Stack card in alternate stacker 2.
Model 7140
Stack card in normal stacker.
Stack card in alternate stacker.
Stack card in normal stacker.
If neither validity, data overrun, nor read
verify
error occurs, stack card in normal
stacker; if error occurs, stack card in alter-
nate stacker.
Stack card in alternate stacker.
Same as 'OE'.
tModels 7121/7122
accept all the above order codes but offer no alternative stacking since they have only one stacker.
READ CARD AUTOMATIC
The orders (hexadecimal code) listed in Table 4 cause the
card reader to feed and read a card in the automatic mode,
with the card
being directed to one of the multiple stackers.
To facilitate reading of intermixed EBCDIC and binary card
decks, card column 1 is sensed for the presence of punches
in rows 1 and
2; if both are present, the read operation is
automatically forced to the binary read mode and all data,
including column 1, is transmitted as described previously
under
"B inary Card Format".
In the EBCDIC card format, 80 bytes are present on a card.
Incorrect length will be signaled if either fewer or more
than 80 bytes
are requested for an EBCDIC card. However,
if the binary read mode is invoked automatically, incorrect
length will be signaled if either fewer or more than 120
bytes are requested.
KEY EVENTS
The key events that occur during a card read operation are
described in the following paragraphs. No chronological
order should be assumed from the order of presentation.
Timing information is discussed under "Programming
Considerations" •
START INPUT/OUTPUT
A card read operation is initiated with the execution of a
START INPUT/OUTPUT instruction by the controlling sys-
tem. If I/O address recognition exists and the reader is in
the "ready" condition with no interrupt pending, the con-
trolling system sets its "I/O address recognition" and "510
6 Key Events
accepted" indicators. The card reader advances from the
"ready" to the "busy" condition and, if the reader is in the
"automatic" mode, it requests an order byte from the con-
trolling system. Note that "510 accepted" does not mean
that the card reader has started to feed and read a card.
"510 accepted" signifies only that a device has accepted
the 510 instruction and the device was in the "ready" con-
dition with no interrupt pending.
UNUSUAL END CONDITIONS
The detection of any of the following during the "busy" con-
dition causes the card reader to return an "unusual end" indi-
cation to the controlling system at the time the condition
occurs:
1.
Invalid order code
2. Read station malfunction
3. Transport mechanism malfunction
4. Absence (or
failure) of ac and/or dc power in reader
5. Operator pressing the RESET switch
6. The occurrence of a data overrun
7. lOP Halt (not applicable to Sigma 2)
CHANNEL END CONDITIONS
After receiving an order from the control Iing system, the
card reader signals "channel end" to the controlling system
when
the end of the card is encountered or an "unusual end"
condition occurs, whichever occurs first.

ERROR CONDITIONS
The card reader is capable of detecti ng and reporti ng the
following error conditions to the controlling system: incor-
rect length, inval id EBCDIC punches, data overrun, and
read verify (Mode I 7140-02) errors.
INCORRECT LENGTH
Incorrect length is caused by the card reader encountering
end of card prior to the "count done" signal from the con-
trolling system or by the occurrence of the "count done"
signal prior to reading column 80 of the card. Thus, ex-
actly 120 bytes must be requested for the binary read mode
and
exactly 80 bytes must be requested for the EBCDIC read
mode; otherwise, an incorrect length condition will be sig-
naled to the controlling system. However, the card is al-
ways directed to the stacker specified by bits 2 and 3 of the
Read
order.
INVALID EBCDIC PUNCHES
When the card reader has received a Read Automatic order
and column 1 of the card does not have punches in rows 1
and 2,
any punch configuration (including column 1) that
cannot be converted into 8-bit EBCDIC (i.e., more than
one punch in rows 1-7) is considered inval id. Detecting an
invalid EBCDIC punch configuration causes the card reader
to generate eight zeros as the data for the invalid column
and to request the controlling system to check parity, in
which case the controlling system sets its Transmission Data
Error indicator to 1. (Xerox 530 and Sigma 2/3 indicate
validity errors by setting the parity error (E) flag in the odd
channel register, not the transmission data error (TE) flag in
the even channe I register.) If the Read Automati corder
specified error stacking, an invalid EBCDIC punch config-
uration causes the card to be di rected to a I ternate stacker 2
(Model 7120) or the alternate stacker (Model 7140).
DATA OVERRUN
A data overrun (rate error) is defined as failure of the con-
trolling system to service the card reader at the required
data transfer rate. If the Read order specified error stacking,
a data overrun causes the card to be directed to al ternate
stacker 2(Model 7120) or the alternate stacker (Model 7140).
READ VERIFY (MODEL 7140-02)
A read verify error is caused by fai lure of the card reader to
read the same data at both read stations. If the Read order
specified error stacking, a read verify error causes the card
to be directed to the alternate stacker.
NOT OPERATIONAL CONDITIONS
A "not operational" condition, generally, is any condition
that causes a peripheral device to switch to the "not opera-
tional" state. For the card reader, any of the following
fault conditions (singly or in combination) may occur during
a
card read cycle:
1. Read station malfunction.
2. Transport mechanism malfunction (i.e., card jam).
3. Absence (or failure) of ac and/or dc power in the
reader.
CARD READERSTATUS RESPONSE
The card reader system is capable of returning various status
flags in response to computer-executed I/O instructions.
Detailed explanations of the input/output instruction to re-
quest status of the card reader are contained in the reference
manuals for Xerox computers. The following paragraphs
explain the significance of each status flag returned to the
contro II ing system by the card reader.
1/0 INSTRUCTION STATUS BITS
The execution of an I/O instruction by the controlling sys-
tem provides two bits of
immediate information pertaining to
the
general status of the addressed I/O device and its con-
troller. This information is retained by the controlling sys-
tem in a form
that allows for conditional branching based
on
the response to the I/O instruction. Table 5 lists the
I/O instructions, the possible status bit settings provided by
each I/O instruction, and the significance of each setting.
DEVICE STATUS BYTE
Eight bits of information in the Device Status Byte are made
avai I able to the computer in response to the execution of an
I/o instruction, as shown in Tables 6, 7, and 8.
OPERATIONAL STATUS BYTE
In addition t~ the information contained in the Device
Status Byte, the Operational Status Byte generated at the
end of each I/O operation a Iso provides indi cators to the
controlling system (see Table 9).
PROGRAMMING CONSIDERA liONS
SEQUENCE OF ACTIVITY
Figure 3 illustrates the sequential relationship of the key
events that occur during a card reading operation.
TIMING INFORMATION
Figures 4, 5, 6, and 7 illustrate the time-dependent events
occurring during a card reading operation for the respective
models.
Card Reader Status Response/Programming Considerations 7

Table 5. Card Reader I/O Instruction Execution Response
Status Bitst
Instruction CCI or 0 CC2 or C
Significance
SIO a a I/O address recognized and SIO accepted.
a I
I/O address recognized, but SIO not accepted.
1 a Selector lOP is "busy" (appl icable only to Si gma 5/6/7).
1 1
I/O address not recogni zed.
HIO a a I/O address recognized and card reader "not busy" when
halt occurred.
a 1
I/O address recognized and card reader "busy" when halt
occurred.
1 a Invalid code.
I 1 I/O address not recogn ized.
no 0 a
I/O address recognized and SIO can currently be accepted.
a 1
I/O address recognized, but SIO cannot currently be accepted.
I a -
Selector lOP is "busy" (appl icable only to Sigma 5/6/7).
1 1
I/O address not recognized.
TDV
a a
I/O address recognized.
a 1 Invalid
code.
1 a Sel
ector lOP is "busy" (appl i cab Ie onl y to Si gma 5/6/7).
1 1
I/O address not recognized.
AIO a 0 Normal interrupt
condition present (no "unusual end").
a 1 Unusual interrupt ("unusual
end") condition present.
1 a Invalid
code.
1 1
No interrupt condition present.
t
In Xerox 530 and Sigma 2/3 computers, "0" represents the Overflow bit and "C" represents the Carry bit; in other
Xerox
computers,I"CCl" and "CC2" refer to condition code bits.
8 Card Reader Status Response

Table 6. Device Status Response for 510, no, and HIO
Bit
Position
Function
State
Meaning
0
Interrupt Pending
1
Interrupt is pending (that is, issued but
not yet acknowledged
by an AIO instruction).
A new order wi II not be accepted
until the interrupt is cleared by an AIO or HIO instruction
or by manual intervention (I/O reset from computer control
panel).
Command chaining,
if specified, will initiate a
new
read card cycle even though an interrupt may be
pending.
1,2
Device Condition
A combination of these two bits indicates the current reader
condition.
00
Card Reader Ready.
o1
Card Reader Not Operational -manual
intervention
re-
quired to clear "not operational" condition.
1 0
Device Unavailable - not applicable.
1 1
Card Reader Busy.
3
Mode
0
Card reader in "manual"
mode (manual intervention
I
requi red).
1 Card reader in "automatic"
mode.
4 Unusual End 1
Execution of previous order terminated due to abnormal
condition, as listed under "Unusual End Conditions".
(Xerox 530 and Sigma 2/3 do not signal
"unusual end"
when an invalid EBCDIC punch is detected.)
5,6 Controller Condition
Same configurations as bits 1,2.
7 Reserved 0 This
bit is currently zero; however,
it may be used in future
enhancements.
Table 7. Device Status Response for TDV
Bit
Position Function
State Meaning
0 Data Overrun
1
Data overrun occurred since previous order received by card
reader.
1
Validity Error 1 Va Iidi
ty error occurred since previous order recei ved by
card reader.
2 Read Verify Error (Model 7140)
1 Read
verify error occurred since last order issued by control-
ling system.
3-7
Reserved 0 These bits
are currently zeros; however, they may be used in
future enhancements.
Card Reader Status Response 9

Table 8. Device Status Response for AIO
Bit
Position Function
State
Meaning
0 Data Overrun
1
Data Overrrun occurred since previous order received by
card reoder.
1-7
Reserved 0 These bits
are currently zeros; however,
they may be used
in future
enhancements.
Table 9. Operational Status Bytet
Function
State Meaning
Incorrect Length 1
Incorrect length condition occurred since previous order was received
by card reader.
Transmission Data Error 1 Invalid EBCDIC punch encountered during automatic read operation,
data overrun occurred, and/or read verifyerror (Model 7140-02) occurred
si nce previous order recei ved by card reader. (Xerox 530 and
Sigma 2/3 indicate invalid EBCDIC punch by setting parity error
(E flag) in the odd channel register, not the transmission data error
(TE flag) in the even channel register.)
Channel End
1
Card reader terminated its operation for any reason listed under "Chan-
nel End Conditions".
Unusual End
1
Card reader terminated its operation for any abnormal condition listed
under "UnusuaI End Conditi ons". (Xerox
530 and Si gma 2/3 do not
signal "unusual end" when an invalid EBCDIC punch is detected.)
tFor the bit positions of these functions in the Operational Status Byte,
see the applicable Xerox Computer Reference
Manual.
10 Card Reader Status Response

CONTROLLING SYITEM ACTIONS
ISet Unc'cal End lndka.a'.1 '"'4o-------~
!~td~~t:~:r~u~:c~;::ns- I
mission Data Error, and r - - -
Unusual End indicators. I
I
Advance to "busy"
condition.
I
I
CARD READER ACTIONS
Stop transport motor,
light FEED' indicator,
and switch to "not
operational" stote.
Stock cord in error
stocker, 1;9~t READ'
--+------------'-----1 indicator, and sw;tch to
"not operational" state.
If ~evious column data not
sent when next column is at
read stotion, 0 data overrun
condition has occurred.
Set TransrniHion Doto
Error indicator.
t---------
Set Incorrect Length
indicator.
I
Set ChaMel End
indicator.
1-------
IFor Model 7120, FAULT indicator.
ttModel 7140 reads each cord column twice and then
compores the dato. If dota read from read stotions is
not the same, Read Verify and Transmission Data error
indicators ore set,
Stop tramport motor ond
switch to "not opera-
tional" state,
Wait for next 5[0 (or
next order, if controlling
sy$tem command chains),
Figure 3. Controlling System/Card Reader Actions
Programming Considerations 11

Time (in milliseconds) Event
O ...... ---,...--.-----------Card reader receives valid read order and reader is in "busy automatic" state.
10
20
30
40
50
60
70
80
90
100
110
120
130
140
B
I------ii;--------- Column 1 arrives at read station. Mode change (EBCDIC to binary) will occur at
this time if rows 1 and 2 are punched.
C
Column 80 arrives at read station.
End of card is detected; card reader signals "channel end" to controlling system.
Card
reader returns to "ready" condition (a new 510 can be accepted if no in-
terrupt is pending) unless the controlling system specifies command chaining, in
which case the reader requests a new read order.
150 +---+---------
Card advances from read station to stacker station. New feed cycle begins at
this time if new valid order is present and reader is still in the "automatic" mode.
160+--''------------- Card is stacked in preselected stacker or in error stacker (alternate 2).
Notes
®
®
©
If the feed cycle begins while the previous card is being stacked, a stacker transport jam occurring in this time
interval causes the reader to stop the transport motor, switch to "not operational", light the FAULT indicator,
and signal "unusual end" to the controlling system.
Feed
cycle (approximately 43 milliseconds).
The data bytes are transmitted, with respect to the col umn read time (approximately 1.34 mi II iseconds), as follows:
odd column even column odd column
Column read
pu Ises
EBCDIC mode:
Binary mode:
transmit one
byte
for each col umn
Transmit rows 12-
5J
Save rows 6-9
lTransmit rows 2-9
Transmit rows 12-1 plus rows
6-9 of previous column
@ If stacker jam occurs after new feed cycle begins, action during this interval is identical to note A. If stacker
jam occurs before new feed cycle begins, reader turns off transport motor, switches to "not operational" state,
and lights FAUL T indicator ("unusual end" is not signaled in this case).
Figure 4. Card Reader Event Times (Model 7120)
12 Programming Considerations

~~
/~----
Time (in milliseconds) Event
o
16
Card reader receives valid read order and reader is in "busy automatic" state. Light check occurs
--.------- at this time. If light check fails, the read indicator will light, the reader will switch to "not op-
erational" and an "unusual end" will be signaled to the controlling system.
50
4
"'7-j_+-1- _____ Column 1 arrives at read station. Mode change (EBCDIC to binary) will occur at this time if rows
1
and 2 are punched.
60
70
80
90
100
110
210
220
230
240
_..L- ______ Column 80 arrives at read station.
End of card is detected; card reader signals "channel end" to controlling system. Card reader
returns to "ready" condition (a new SIO can be accepted if no interrupt is pending) unless the con-
troll ing system specifies command chaining, in which case the reader requests a new read order.
250 ---®-- New feed cycle enabled at this time ifnewvalid order present and readerstill in "automatic" mode.
Notes: ® Feed cycle is usually approximately 47 ms but can be as long as 200 ms (in case of slippage or slight jam).
If a card has not been fed after 200 msec, the transport motor wi II halt, the reader wi II switch to "not op-
erational", the FEED indicator will light, and an "unusual end" will be signaled to the controlling system.
® The data bytes are transmitted, with respect to the column read time (approximately 2.05 ms), as shown
below.
l-- 2. 05 ms ---J-- 160 ms--l
Data available to controlling system
Col. 1 ~
t t
EBCDIC mode: Transmit
one byte n n n
for each col umn -.-11 ______ -' L ______ -' '- ___ _
~ llil nJl_
Binary mode: Transmit rows
12-5 ~ 1 L
©
@
®
®
Store rows 6-9 Transmit rows 2-9
Transmit rows 12-1 plus
rows
6-9 of previous column
t indicates data overrun will occur at this time if data is not accepted by controlling system.
Throat jam
detection occurs 215 ms later if card jams in throat area, causing transport motor to halt, FEED
indicator to light, reader to switch to "not operational", and an "unusual end" to be signaled to contror-
ling system.
Read and timing jam
detection occurs 225 ms later if card jams in read and timing area. Results in same
action as © above.
Dark check occurs at this time. If dark check fails, the READ indicator will light, the reader will switch to
"not operational", and an "unusual end" wi \I be signal ed to the controlling system.
Stacker jam detection occurs 215 ms later if card jams in stacker area. Results in same action as © above.
Figure 5. Card Reader Event Times (Model 7121)
Programming
Considerations 13

Time (in milliseconds) Event
·0
-,--,-------Card reader receives valid read order and reader is in "busy automatic" state. Light check
10 C
20-~.
occurs at this time. If light check fails, the read indicator will light, the reader will switch
to
"not operational" and an "unusual end" will be signaled to the controlling system.
I-~
30 -tl-f----....;;...,---Column 1 arrives at read station. Mode change (EBCDIC to binary) will occur at this time if
40 _ rows 1 and 2 are punched.
50 -
60 -
70 -B
80 -
90 -
100 -
110 -
-l~---'------- Column 80 arrives at read station.
120 -
130 -
140
--1-------0
End of card is detected; card reader signals "channel end" to controlling system. Card reader
returns to "ready" condition (a new SIO can be accepted if no interrupt is pending) unless the con-
trolling system specifies command chaining, in which case the reader requests a new read order.
150 -"1
________ New feed cycle enabled at this time if new valid order present and reader still in "automatic"
Notes:
®
®
©
@
mode.
Feed
cycle is approximately27ms if card feeds on first attempt, approximately 87ms if card feeds on
second
attempt, and approximately 147ms if card feeds on third attempt. If a card has not been fed after
three attempts, the transport motor will halt, the reader will switch to "not operational", the FEED
indicator will light, and an "unusual end" will be signaled to the controlling system.
The
data bytes are transmitted, with respect to the col urnn read time (approximately 1.12 ms), as shown below.
1- 1.12 ms -1- 98 ms -I
Data available to controlling system ~
t U U
1
EBCDIC mode: Transmit one byte
for each column
~,-- ___ n,-- __ ----,n,-- __
~ nJl n'----_
Binary mode: Transmit rows 12-5 ____ ---'1 t r
Store rows 6-9 I ~- ---Transmit rows 2-9
Transmit rows 12-1 plus
rows
6-9 of previous column
t indicates data overrun will occur at this time if data is not accepted by controlling system.
Throat jam
detection occurs 125 ms later if card jams in throat area, causing transport motor to halt, FEED
indicator to light, reader to switch to "not operational", and an "unusual end" to be signaled to the
controlling system.
Read and timing jam
detection occurs 125 ms later if card jams in read and timing area. Results in same
action as © above.
® Dark check occurs at this time. If dark check fails, the READ indicator will light, the reader will switch
to
"not operational", and an "unusual end" will be signaled to the controlling system.
® Stacker jam detection occurs 125 ms later if card jams in stacker area. Results in same action as © above.
Figure 6. Card Reader Event Times (Model 7122)
14 Programming Considerations