RDCARD Macro
RDCARD Use the RDCARD macro instruction to read a line from a virtual card
reader. The format of the RDCARD macro instruction is: r , I [label] I RDCARD I buffer[,length][,ERROR=erraddr] I L, ____ , label
buffer
length
is an optional statement label.
specifies the buffer address into which the card is to be
read. It may be:
bufaddr
(reg)
the symbolic address of the buffer.
a register containing the address of the buffer.
specifies the length of card to be read. If omitted, 80 is
assumed. The length may be specified in one of two ways:
n
(reg)
a self-defining term indicating the length.
a register containing the length.
ERROR=erraddr
specifies the address of an error routine to be given
control if an error is found. If ERROR= is not coded and an
error occurs, control returns to the next sequential
instruction in the calling program, as it does if no error
occurs.
1. No stacker selecting is allowed.
2. When the macro completes, register 0 contains the length of the
card that was read.
3. You may not use the RDCARD macro in jobs that run under the eMS batch machine.
If an error occurs, register 15 contains one of the following error
codes:
Code --1- 2
3
5 100 !1g§:.ning End of file
unit check Unknown error
Length not equal to requested length
Device not attached
Section 6. CMS Macro Instructions 333

RDTAPE RDTAPE Use the RDTAPE macro instruction to read a record from the specified
tape drive. The format of the RDTAPE macro instruction is:
r---------------- ------------------------, , (label] , RDTAPE buffer,length [,device] , , , [ , ERROR;erradr] I L __ _
label bu ffer
length
device
is an optional statement label.
specifies the buffer address into which the record is to be
read. It may be specified in either of two ways:
the symbolic address of the buffer. lineaddr
(reg) a register containing the address of the buffer.
specifies the length of the largest record to be read. A 65,535-byte record is the largest record that can be read. It may be specified in either of two ways:
n (reg) a self-defining term indicating the length.
a register containing the length.
specifies the device from which the line is to be
omitted, TAPl (virtual address 181) is assumed.
specified in either of two vays:
read. If
It may be TAPn indicates the symbolic tape number (TAP1 through TAP4) • cuu indicates the virtual device address. specifies the number of tracks, density, and tape recording
technique options. It must be in the following form:
([ track ],[ density], [trtch])
ER RDR=er ra ddr
track 1 indicates a 1-track tape (implies density;800 and trtch;O) • density
trtch
9 indicates a 9-track tape (implies density;800). 200, 556, or 800 for a 7-track tape. 800, 1600, or 6250 for a 9-track tape.
indica tes the
1-track tape.
specified:
tape recording technique for
One of the following must be
o -odd parity, converter off, translator off.
DC -odd parity, converter on, translator off. OT - odd parity, converter off, translator on.
E -even parity, converter off, translator off.
ET -even parity, converter off, translator on.
specifies the address of an error routine to be given control
if an error is found. If ERROR= is not coded and an error
occurs, control returns to the next sequential instruction in
the calling program, as it does if no error occurs. 334 Command and Reference