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Protocol converter model a/s-4 – Black Box PROTOCOL CONVERTER A/S-4 User Manual

Page 43

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PROTOCOL CONVERTER MODEL A/S-4

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6.11.1 C

HANGING

I

NTERACTIVE

A

PPLICATION

O

PTIONS

The change Application menu allows 8 operations as described below:

A. Exit - By entering the letter A the A/S-4 will return to the Main Menu.

B. XID - By entering a B the operator is able to change the A/S-4 SDLC control unit identifier. Only

hexadecimal numbers are allowed to be entered for this selection, the first two digits are fixed at 01.
The next character indicates what type of device the A/S-4 (7=3274, 8=3276, 0=3774, 1=3774P,
2=3771 and 3=3776/77).

C. PU Addr - To change the units physical unit address enter C. Only hexadecimal numbers are allowed

to be entered for this selection; addresses x’00’-SSCP address and x’FF’-Global SDLC address can not
be used.

D. SDLC Baud Rate - By entering a D the operator can select the baud rate at which the host will

transmit and receive data from the A/S-4. This selection is only used when running SDLC over
asynchronous modems or when the A/S-4 is supplying clocks to a front end processor. After entering
the letter D the current baud rate will be displayed. To change it, enter the letter Y which will scroll
pass each selectable baud rate, when the correct rate is displayed entering any key other than the Y
will save the new baud rate.

NOTE

SDLC baud rate has no effect when running with synchronous modems.

E. XON/OFF - Entering an E allows the selecting of the DC1 (XON), DC3 (XOFF) protocol on the

A/S-4’s terminal port. This protocol can be used; TO the unit or FROM the unit or in BOTH
directions. To disable the XON/OFF protocol, select the option for OFF by the use of the letter Y,
entering any key will save the selection. This protocol is used so the A/S-4 or the attached async
device will not overflow each others buffers with data. If the A/S-4 has room to store only 20
characters from the VDU, the unit will drop it’s RTS signal (can be connected to pin 4, 5, 11, 19 or 20
of EIA connector) and send an XOFF character if option is set for FROM or BOTH. When the A/S-4
is sending data to the VDU, the VDU can stop the flow by dropping it’s signal connected to the A/S-
4’s CTS or by sending a XOFF character, if the A/S-4’s XON/XOFF option is set for TO or BOTH.

F. VDU LU Addr - The VDU LU address can be changed by entering the letter F. For this selection only

hexadecimal numbers are allowed to be entered, from the range of X’01’ to X’FF’ but for most
installations the address range of the specific type of control unit is as follows:

IBM* 3274 = X’02’-X’21’
IBM* 3276 = X’02’-X’09’
IBM* 3776 Model 3 and 4 = X’01’-’06’

NOTE

Do not set the VDU and PRT LU addresses to the same values.