6100 ADCCP Programming Manual

6100 ADCCP Concepts and Context
Introduction to 6100 ADCCP
1–16 069225 Tandem Computers Incorporated
SABM This command can be used by either one or both combined stations on a
link. It places the link in asynchronous balanced mode. The expected
response is UA. The Ns and Nr counts are reset to zero when this
command is accepted, and the stations are free to transmit data. The
stations stay in ABM until either one transmits a DISC command or another
mode setting command.
SABME This command is the same as SABM, except that it implies the extended
control field format. It does not necessarily imply an extended address
field.
SARM This command is used by a primary station to place a link in ARM. The
expected response is UA. The Ns and Nr counts of both stations are reset to
zero. The link stays in Asynchronous Response Mode until the primary
issues a DISC command or any other mode setting command.
SARME This command is the same as SARM, except that it implies the extended
control field format.
SIM This command is used by the primary station to trigger device-dependent
initialization activities within a secondary station. UA is the expected
response. The Nr and Ns counts are reset to zero when this command is
accepted.
SNRM This command is issued by a primary station to a secondary station, and
places the secondary in NRM. (The primary station must issue this
command to each secondary it polls.) The expected response is UA. The
Ns and Nr counts of both stations are reset to zero when this command is
accepted. The secondary stays in NRM until the primary sends it a DISC,
SIM, or a mode setting command.
SNRME This command is the same as SNRM, except that it implies the extended
control field format.
TEST This command can be used by either a primary station or a secondary
station to test the link.
UA A secondary station sends this frame in answer to a SIM, SABM, SARM,
SNRM, SABME, SARME, SNRME, or DISC command.
UI A primary or secondary station can transmit one frame of information with
this frame type. The information is transferred between the stations with
no link-level acknowledgment. Most applications do not use this frame
type.
USER0 This is a user-defined frame type as defined in the ANSI ADCCP standard.
I-fields are allowed in this frame.
USER1 This is a user-defined frame type as defined in the ANSI ADCCP standard.
I-fields are allowed in this frame.
USER2 This is a user-defined frame type as defined in the ANSI ADCCP standard.
I-fields are allowed in these frames.