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Chapter 7 - DIP-Switch Settings
Switch #2
SDLC/BSC Option
(Synchronous Mode/Leased Line/Dial-Up)
Synchronous Data Link Control (
SDLC
) and Binary Synchronous Control (
BSC
) are two error
correction protocols used in the IBM Mainframe environment. Place DIP-Switch #2 in the UP position
to enable SDLC mode, and place DIP-Switch #2 in the DOWN position to enable BSC mode.
SDLC Mode = Switch #2 UP
BSC Mode = Switch #2 DOWN
Factory Default Setting = UP
Switch #3
Enable/Suppress Responses -- "Q"
(Asynchronous Mode/Dial-Up)
In some Asynchronous mode applications, you may want to suppress all responses from the modem.
Place DIP-Switch #3 in the DOWN position to enable Result Code responses (
Q0
). Place DIP-Switch
#3 in the UP position, and answer mode is handled without responses and echo turned off (
Q2
), but
originate is still intelligent.
Enable Responses: Originate/Answer (
Q0
) = Switch #3 DOWN
Suppress Responses: Answer (
Q2
) = Switch #3 UP
Factory Default Setting = DOWN
Switch #3
dB Transmission Levels
(Asynchronous/Synchronous Mode/Leased Line)
DIP-Switch #3 adjusts dB transmission levels required by some phone carriers. Place DIP-Switch #3
in the DOWN position to enable -9 dB transmission. Place DIP-Switch #3 in the UP position to enable
-15 dB transmission.
-9dB Transmission = Switch #3 DOWN
-15dB Transmission = Switch #3 UP
Factory Default Setting = DOWN
Switch #4
AS/400 Mode
(Synchronous Mode/Leased Line/Dial-UP)
The modem can function in the IBM AS/400 environment (appearing like an IBM5853 modem). First,
DIP-Switch #7 must be placed in the UP position. This establishes an RTS/CTS condition (state
typical for an IBM5853 modem in half-duplex mode). Next, place DIP-Switch #4 in the DOWN
position. This
"spoofs"
the modem into operating like an IBM5853 modem in AS/400 applications.
DIP-Switch #4 in the UP position disables this function. Note that the modem must be in Command
mode to allow AS/400 mode (DIP-Switch #8 DOWN); and in Synchronous mode (DIP-Switch #12
UP).
AS/400 Mode Enabled = Switch #4 DOWN
AS/400 Mode Disabled = Switch #4 UP
Factory Default Setting = UP