Binary Data Transmissions/ Receptions; Component Selection - Texas Instruments 990 User Manual

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For the IBM 3780 and 2780. all 256 eight-bit combinations, including binary data, may be
transmitted or received in transparent mode. For the Emulator, transparency enabled means that the
entire seven-bit ASCII code set may be transmitted or received. To transmit or receive binary data
(or all 256 eight-bit combinations) with the Emulator, the special identifier # (pound sign) must
precede the file pathname or text string. This special identifier indicates to the Emulator that it
should not translate from ASCII to EBCDIC as it normally would. Refer to paragraph 2.2.13,
Binary Data Transmissions/ Receptions, for further information.
2.2.13 BINARY DATA TRANSMISSIONS/RECEPTIONS. In a 990 to 990 communication
environment, the Emulator can transmit and receive binary data using the Send Data (S), Send Data
with Device Selection (SS). Receive Printer Data (RPR), and Receive Punch Data (RPU)
commands (these commands are described further in Section IV, paragraphs 4.5.3.1, 4.5.3.2. 4.5.4.1,
and 4.5.4.2, respectively). The binary specification may also be used on nonbinary files. The binary
specification in this case means do not translate this file from ASCII to EBCDIC and back as the
Emulator normally would. This enables the Emulator to transmit and receive all 256 eight-bit
combinations (the entire EBCDIC code). Binary specification, also allows the transfer of DXIO
program files.
Binary is specified using a# (pound sign). The pound sign precedes each pathname being transmitted
or received. For further information about sending and receiving binary files, refer to paragraphs
4.5.3 and 4.5.4, respectively.
2.2.14 COMPONENT SELECTION. The component selection feature permits the i'.mulator and
the IBM 3780 and 2780 to have their output devicc(s) selected by the transmitting station. Selection
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made via a component selection code sent by the transmitting station. If no component selection is
made, received data is directed to the printer. ·
The 3780 Emulator has two selection codes for the card punch. Either a DC2 or DC3 may be selected
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the card punch at installation time. The selection code chosen for the local station's card punch
should match the card punch selection code of the remote station.
The 3780 Emulator selection code for the printer is DC I.
The 3780 Emulator selection code is valid only if it is received as the first text characters of the first
block of text, whether that block is:
• Received after transmitting a positive response to a line bid.
• The first block of a conversational reply.
• The first block following an ETX block.
If the selection code is not transmitted in this manner, it is handled as data.
The 2780 Emulator card punch selection code is ESC4. The printer selection code is any of the valid
EBCDIC printer ESC sequences shown in table 2-2.
The 2780 Emulator selection code must be received as the first two characters of the first record of a
nontransparent transmission block or as the first two characters following the first STX in a
nontransparent block of data. The selection code may be included in other records also. To use the
selection code for transparent data, first send th·e selection code alone in nontransparent mode. then.
send the subsequent blocks as transparent data. The selection code will remain in effect until another
selection is made in nontransparent mode or until an EQT (End of Transmission) is sent.
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Digital Systems Group