If the data code expressed by
WIFl
to WIF8 is
X'6C',
X'6D',
or
X'6E'
when
the Paper Instruction signal is 1, the printer treats the data code as the
start code for FCB data loading and loads into the FCB the data following
the start code, until the printer receives the stop code
X'6F'.
The stop
code is
also
sent with the Paper Instruction signal.
The transferred data is first loaded into the print data buffer
(PDB)
in
the IBF.
Then the interface control
(IFC)
microprogram loads the data
into the FCB and knows the number of lines per page by counting the loaded
FCB data bytes.
Table 4.3 shows the definition of the start code.
Table 4.3 Definition of the start code
WIF
_ Code Operation
87654321
oiex)
I
01101100 6C
Line spacing is 6
Ipi.
:
1
Six or eight
lpi
specification from
01101101
6D
Line
specing
is 8 lpi.
I
ehe
operaror
panel ignored.
01101110 6E
Forms are fed in 618 lpi when specified
ac
the operator panel.
Note:
WIF8 is ignored and treated as 0 in 7-bit mode.
In Figure 4.8, L1H1L2H2...LnHn (2
_
_
<
n
<
2.55)
is the format control FCB
data.
Each L or H is one byte of data. Each pair
Iof
an L and H is format
control data for one line on the form.
LiHl
is data for line 1,
L2H2
is
data for line 2, and
so
forth.
L,H,
is data for the last line, and
n
indicates the total number of lines on a form (page.). The first byte
(L)
of the 2-byte line format data specifies a channel
:number
from 1 to 6 and
the second byte
(H)
specifies a channel number from 7 to 12. Figure 4.9
shows the correspondence between channels and
WIFl
to WIF8.
Data L
Data H
WIF
signals
Specified
channel
8765432,
8
7
6
,5
4 3 2 1
I--Ix0L-I
II I
I
6
5
4
3
?
1
Note:
X do not care. (In 8-bit mode)
Figure 4.9 Correspondence between FCB data channels and bits
B02P-1500-OOOlA...05 4
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13