A-7
A1
A
EOI (end or identify) is used by a device to indicate the end of a
multiple-byte transfer sequence. When a controller-in-charge sets
both the ATN and EOI lines true, each device configured to respond
to a parallel poll indicates its current status on the DIO line assigned
to it.
Bus Commands are transmitted when ATN is asserted. The commands
are listed in the message columns in Table 1 (on the left hand page)
which shows the relationship between the commands and ASCII data
characters. ASCII data characters have the same code values as bus
commands but are transmitted with ATN off. The following chart
lists the standard command and address mnemonics.
Address Commands
MLA My listen address (controller to self)
MTA My talk address (controller to self)
LAD Device listen address
TAD Device talk address
SAD
Secondary Device address (device optional address)
UNL Unlisten
UNT Listen
Universal Commands (to all devices)
LLO Local Lockout
DCL Device Clear
PPU
Parallel Poll Unconfigure
SPE
Serial Poll Enable
SPD
Serial Poll Disable
Addressed Commands (to addressed listeners only)
SDC
Selected Device Clear
GTL Go to Local
GET Device Trigger
PPC
Parallel Poll Configure
TCT
Take Control
