hi-6131pqtf QuickLogic Corp, hi-6131pqtf Datasheet - Page 208

• Manufacturer Part Number: hi-6131pqtf
• Description: Mil-std-1553 / Mil-std-1760 3.3v Bc / Mt / Rt Multi-terminal Device
• Manufacturer: QuickLogic Corp

21. REMOTE TERMINAL RT1
21.1. General Considerations
The device provides decoding for all mode code combi-
nations, consistent with MIL-STD-1553B requirements.
Several mode command options are provided to suit any
application requirement:
In Configuration Register 1, the option bit UMCINV (Un-
defined Mode Codes Invalid) globally defines whether
undefined mode code commands are treated as valid
(default) or invalid commands. This bit applies only to
the following 22 mode code commands that are unde-
fined in MIL-STD-1553B:
If the UMCINV bit is low (default after MR reset) unde-
fined mode code commands are considered valid and
RT response is based on individual mode command set-
tings in the Illegalization Table: If the command’s table bit
equals 0, the mode command is legal; the RT responds
“in form” and updates status. If the command’s table bit
equals 1 the mode command is illegal, the RT asserts
Message Error status and (if non-broadcast) transmits
only its Status Word without associated data word. Table
17 describes explicit terminal response for each mode
code value and command T/R bit state, based on vari-
ous option settings.
If UMCINV is asserted, the 22 undefined mode code
commands are treated as invalid: There is no terminal
recognition of the command. No command response oc-
curs and status remains unchanged for the benefit of
following “transmit status” or “transmit last command”
mode commands.
If UMCINV is low, the device determines legal vs. illegal
status of commands from the Illegalization Table. If the
terminal does not use illegal command detection, the Il-
legalization Table should be left in its post-reset default
state, all values equal logic 0. In this case, the terminal
provides “in form” response to all valid commands. The
terminal responds with clear status and a transmitted
mode data word for mode commands 16-31 with T/R bit
equals 1. Assigned data buffer locations can be initial-
ized to provide predictable “in form” responses for all
transmit mode codes 16-31. (If UMCINV is asserted,
the terminal will not respond or update status for re-
ceived mode codes 17, 20 and 21 with T/R = 1.)
AND RT2 MODE COMMAND
PROCESSING
Mode Codes 0 through 15 with T/R bit = 0
Mode Codes16, 18 and19 withT/R bit = 0
Mode Codes 17, 20 and 21 with T/R bit = 1
HOLT INTEGRATED CIRCUITS
HI-6130, HI-6131
208
To use illegal command detection, the host modifies the
Illegalization Table to make illegal any combination sub-
address and mode code commands. This may include
undefined mode codes, reserved mode codes, and/or
mode codes not implemented in the application.
Note: Mode command MC0 “dynamic bus control” can-
not be implemented in the device since the HI-6130/21
cannot act as a Bus Controller. Therefore, the “dynamic
bus control acceptance” status bit cannot be set in the
outgoing status word from this device.
21.2. Mode Command Interrupts
For mode commands, interrupt generation is pro-
grammed by the top three bits in the descriptor table
Control Word. Notice that broadcast-transmit interrupts
can be enabled for mode code values in the range of
0 - 15, but broadcast-transmit mode codes 16 - 31 are
not allowed. When a mode command is received and
the IWA interrupt bit is asserted in its descriptor Control
Word, that command will generate a host interrupt if the
IWA bit is high in the Interrupt Enable Register. The IWA
bit is asserted in the Pending Interrupt Register and the
INTMES interrupt output is asserted.
Before INTMES interrupt assertion, the device updates
the Interrupt Log buffer, writing a new IIW Interrupt In-
formation Word and a new IAW Interrupt Address Word.
The IWA (interrupt when accessed) bit is asserted in the
new IIW to indicate interrupt type. The IAW contains the
Descriptor Table address for the mode command’s Con-
trol Word, based on mode code value and command
word T/R bit state. The host reads the IAW to determine
the command that caused the interrupt.
21.3. Mode Command Data Words
Mode commands having mode code values from 0
through 15 (decimal) do not have an associated data
word. These are received as Command Word only, never
having a contiguous data word. The terminal response
to valid mode commands 0-15 always consists of Status
Word only, assuming command was not broadcast.
Mode commands having mode code values from 16
through 31 (decimal) always have an associated data
word. When the command word T/R bit equals 0, the ter-
minal receives a data word, contiguously following the
Command Word. When valid legal mode commands 16-
31 arrive with T/R bit equal to 1, the terminal responds
by transmitting its status word with a single data word.
When the SMCP option bit in Configuration register 1
is zero, individual data words for mode codes 16-31