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Notes: I/O CONTROL SDS/006
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;…06…;…07…'…0f……1e……01……1e……02……1e……07……1d……08……1d……0f……1d……02……1d……06……1d……07……1c……0b……1c……0c……1c……0d……1c……01……1c……02……1b……08……1b……0d……1b……0e……1b……0f……1b… …1b……05……1a……0b……1a……01……1a……02……1a…
…1a……06……1a……07……19……08……19……0d……19……0e……19…
…19… …18……0a……18……86…1
…02…
…02…
…02…
…02…CPS/SDS/006
…02…HKI/810801…02……02…
I/O CONTROL
…02……02…CAMPS
4.2.3 L̲T̲U̲ ̲H̲a̲n̲d̲l̲e̲r̲ ̲S̲u̲b̲p̲a̲c̲k̲a̲g̲e̲
4.2.3.1 F̲u̲n̲c̲t̲i̲o̲n̲a̲l̲ ̲S̲p̲e̲c̲i̲f̲i̲c̲a̲t̲i̲o̲n̲
4.2.3.1.1 F̲u̲n̲c̲t̲i̲o̲n̲a̲l̲ ̲B̲r̲e̲a̲k̲d̲o̲w̲n̲
The LTU Handler Subpackage implements the definition
of terminals in DAMOS TMS sense for the NICS TARE interface
and the CCIS/SCARS interface.
Furthermore, the LTU Handler performs the generation
of data records (see section 4.1.6) from incoming characters
and converts from data records for outgoing characters.
Figs. 4.2.3.1.1-1 through 9 present the functional
breakdown.
Fig. 4.2.3.1.1-1/9
4.2.3.1.2 F̲u̲n̲c̲t̲i̲o̲n̲a̲l̲ ̲D̲e̲s̲c̲r̲i̲p̲t̲i̲o̲n̲
The Control Functions are Handler Control interface
from TMS including requests for data transfer.
The NICS-TARE interface is defined as two terminals,
one for data and one for Line Control Blocks, where
the CCIS/SCARS interface is defined as one terminal.
Message handling - the NICS-TARE interface to the LTU
is on a segment basis. For outgoing, characters are
collected into segments for transmission, after conversion
of format. Segment size = 512 bytes. For incoming,
the segments are set for conversion and assembled into
messages. The first data returned to the requestor
contains a start of message record, the last an end
of message record.
The CCIS/SCARS interface to the LTU is a data block
interface, where each data block contains an identification
of the transferred message. If the identification changes
in the middle of a message, further input is skipped
and the input requestor notified.
For outgoing CCIS/SCARS, each created data block is
headed by the identification forwarded to the Handler
by the first record of the output.
Data Format Control - the internal CAMPS format of
data is a record format, where each line consists of
a header + data. The external data is not recorded
but can be seen as a continuous data string. The task
of the Format Control is to provide the conversion
to/from the internal CAMPS format.
The record types are for message data type 0,1,4 and
for start and end type 5 and 6. They are all described
in section 4.1.6.
4.2.3.2 S̲o̲f̲t̲w̲a̲r̲e̲ ̲S̲p̲e̲c̲i̲f̲i̲c̲a̲t̲i̲o̲n̲
The LTU Handler is to be seen as two handlers with
a set of shared procedures. This means that the LTU
Handler has four entry points in total for the two
defined handlers:
NICS-TARE Handler
CCIS/SCARS Handler
namely:
1. TMS request NICS-TARE HANDLER
2. LTU interrupt NICS-TARE HANDLER
3. TMS request CCIS/SCARS HANDLER
4. LTU interrupt CCIS/SCARS HANDLER.
Figure 4.2.3.2 gives the hierarchy.
Fig. 4.2.3.2-1/4
4.2.3.3 D̲a̲t̲a̲ ̲F̲l̲o̲w̲ ̲a̲n̲d̲ ̲C̲o̲n̲t̲r̲o̲l̲ ̲L̲o̲g̲i̲c̲
The general data flow/control flow for the two handlers
is shown in figure 4.2.3.3 and is as follows:
For output, the handler works with two buffer types.
One is the handler buffer. It must be located within
the memory space accessible by the CPUs, which means
it must be within the PU or within the LTU. (The actual
location is within the LTU provided the LTU memory
budget allows. If not sufficient space, it is within
the PU). The other is the LTU buffer. It must be located
in the LTU and is accessible by the LTU microprocessor
and the handler.
When by conversion, the LTU buffer is full (either
NICS-TARE segment or CCIS/SCARS data block) the address
is handed to the LTU microprocessor, which will output
the data. When the handler buffer has been emptied
and there are more pending requests, it is returned
asynchroneously to TMS.
If at a TMS output request a buffer is free, it is
immediately returned.
Fig. 4.2.3.3 Handler Data Flow
The input processing is quite similar.
The LTU interrupts the handler with an address of a
full buffer (located in the LTU). The handler converts
the data from the LTU buffer to the handler buffer.
When either the TMS request has been fulfilled (the
application buffer is to be full) or an end of message
or irrecoverable error has occured, the input buffer
is returned to TMS. When the LTU buffer is emptied,
an acknowledgement is returned to the LTU.
4.2.3.3.1 N̲I̲C̲S̲ ̲T̲A̲R̲E̲ ̲F̲l̲o̲w̲
In addition to the described flow above, the NICS-TARE
Handler provides a second terminal for transfer of
Line Control Blocks. Whenever a line control block
is requested transmitted, it is copied into an LTU
buffer and the LTU is notified as above. Whenever an
LCB is handed to the handler by the LTU it is copied
into the LCB buffer and returned to the application
if pending. Otherwise it is returned on next request.
4.2.3.3.2 C̲C̲I̲S̲/̲S̲C̲A̲R̲S̲ ̲F̲l̲o̲w̲
In addition to the general processing in section 4.2.3.3,
the output processing for CCIS/SCARS contains the following:
The message type and precedence are stripped off the
application output request and added to the beginning
of each LTU buffer output for this message.
For input, the incoming buffers contain the message
type and precedence. If these values do not fit with
the message in processing, the input request is terminated
with an error code and subsequent data blocks skipped
until next start of message.
4.2.3.4 S̲u̲b̲p̲a̲c̲k̲a̲g̲e̲ ̲D̲a̲t̲a̲
The LTU handler has the following for NICS-TARE per
channel:
One Control Buffer + One PTCB (Pending Transfer Control
Block).
Two output Handler buffers + 3 PTCBs.
Two input Handler buffers + 3 PTCBs.
One output LCB buffer + 1 PTCB
one input LCB buffer + 1 PTCB
The LTU buffers are dynamically allocated. The handler
has at any moment control of:
0-2 Output LTU buffers.
0-2 Input LTU buffers.
For CCIS/SCARS, the data areas are the same except
that no LCBs are handled.
4.2.3.5 S̲u̲b̲p̲a̲c̲k̲a̲g̲e̲ ̲I̲n̲t̲e̲r̲f̲a̲c̲e̲s̲
The interfaces are outlined in section 4.1.6.
4.2.4 L̲T̲U̲X̲ ̲F̲u̲n̲c̲t̲i̲o̲n̲s̲ ̲S̲u̲b̲p̲a̲c̲k̲a̲g̲e̲
4.2.4.1 F̲u̲n̲c̲t̲i̲o̲n̲a̲l̲ ̲S̲p̲e̲c̲i̲f̲i̲c̲a̲t̲i̲o̲n̲
The functional specification covers only the functions
executed by the application firmware. The LTUX system
firmware is described in: LTUX-S Product Specification
CSD-MIC/220/PSP/0012.
The LTUX is an interface module between the CAMPS TDX
bus and different lines and terminals.
The functional specification is explained by means
of a functional breakdown.
The application functions vary for most of the devices.
The application will be integrated to some extent,
in order to make a single LTUX able to handle several
different lines and terminals.
4.2.4.1.1 F̲u̲n̲c̲t̲i̲o̲n̲a̲l̲ ̲B̲r̲e̲a̲k̲d̲o̲w̲n̲
The functional breakdown is only shown for one LTUX.
This LTUX includes all the functions to be implemented.
An LTUX is interchanged via a bi-directional control
channel and up to four bi-directional data channels.
Fig. 4.2.4.1.1-1 Functional Breakdown
The application functions are divided into six major
groups:
1) Initialize
2) Command Interpret
3) Records to Host
4) Records from Host
5) Line Handling
6) Character error.
1) Initialize
The functions in this group include power up initialize
and restart.
1.1) Initialize Firmware
After power up or after a restart command from the
host, the initalize program in the standard firmware
is activated. The Z80 SIO and CTC are initalized.
1.2) Open Command Channel
The command channel queue buffers are defined and the
command channels are opened by means of a number of
command calls to the standard firmware. Finally, the
application processes are created and activated.
Fig. 4.2.4.1.1-2 Initialize Breakdown
Fig. 4.2.4.1.1-3 Command Interpret
2) Command Interpret
The functions dealing with status request, open / close
channels and restart commands are allocated to the
command interpret module.
2.1) Restart LTUX
This command has the same effect as a power up initialize.
2.2) Open Channel
An open channel command sets up all parameters required
to open a channel.
2.3) Close Channel
A specified channel is closed. The SIO interrupt to
the channel is disabled, the status table updated and
the line handler enabled.
2.4) Status Request
A status request command from the host will result
in a status report.
2.5) Cancel Outgoing Traffic
The outgoing traffic on a specified channel is cancelled
and the buffer contents cleared.
2.6) Command CC
When a command is executed, a completion code is returned
to the sender.
Fig. 4.2.4.1.1-4 Open Channel Breakdown
2.2.1) Allocate Buffers
The number and size of the TDX-packet queue buffers
are defined.
2.2.2) Allocate character queues
The receive and transmit character queues are defined.
2.2.3) Alphabet Converter On / Off
The converter routine ITA 2/5 is enabled or disabled.
2.2.4) Set up Communication Mode
The communication mode is different for most of the
devices:
a) TRC, P-TO-P
CAMPS is DTE
Used V24 lines: 102, 103, 104, 107, 108/2
V24 modem lines: 107, 108/2
CAMPS set 108/2 on, indicate ready
OCR set 107 on, indicate ready
Specific control characters sent to CAMPS:
CR-CR-LF, CR-LF.
The control character sequences are detected by
the record generator and will cause termination
of the present record.
The setup includes definition of legal control
characters.
b) OCR
CAMPS is DCE
Used V24 lines 102, 103, 104, 107, 108/2
V24 modem lines: 107, 108/2
OCR set 108/2 on, indicate ready
CAMPS set 107 on, indicate ready
Specific control characters sent from OCR: STX,
ETB, ETX, CR-CR-LF, CR-LF.
The control characters are detected by the record
generating module and will cause termination of
the present record.
The setup includes definition of legal control
characters.
c) VDU
CAMPS is DCE
Used V24 lines: 102, 103, 104, 105, 106, 107, 108,2
V24 Modem lines: 105, 106, 107, 108,2
Specific control characters sent from VDU: ACK,
BCC, ENQ, EOT, ETX, NAK, STX, WACK.
The setup includes definition of legal control
characters.
2.2.5) Program Z80 SIO/CTC
The Z80 SIO is programmed with a number of parameters:
a) Bits per character
b) Number of stop bits
c) Parity mode
d) Interrupt mode
e) Clock mode
f) Receiver / transmitter enable.
The Z80 CTC is programmed with a channel baud rate
parameter. As the baud rate can only be programmed
for channels in groups of two, an attempt to open the
second channel with a different baud rate from the
first will lead to a refuse of open.
2.2.6) Update Status
The status table is updated. The status table contains
the following information:
a) Command status
b) buffer status
c) Z80 SIO/CTC status
2.2.6.1) Enable Line Handler
The line handler deals with the actual opening and
closing of logical channels and V24 transmission lines.
Fig. 4.2.4.1.1-5 Close V24 Line Breakdown
Fig. 4.2.4.1.1-6 outgoing Records Breakdown
3) Records to Host
The functions implemented include character receive
from Z80 SIO, alphabet converting and message record
formal generating.
3.1) Character Receive
An incoming character to the Z80 SIO will cause a "receive
interrupt". The character will then be transferred
to the receive character queue.
3.2) Alphabet Converter
If enabled, ITA 2 characters will be converted to ITA
5.
3.3) Record Generating
The incoming characters from the receive character
queue will be checked for defined control characters
and defined character sequences. The respective flag
will be set and the message record format terminated.
If an error has occured (including illegal control
character) an end of sequence record is generated indicating
the reason.
3.3.3) Each received character restarts the character
timer
If the incoming data stream stops for more than a preset
time, a time out is generated and the present record
is terminated.
3.4) Record Transfer to TDX Packet Queue
The terminated message record format is transferred
to the TDX packet queue.
Fig. 4.2.4.1.1-7 Incoming Records Breakdown
4) Incoming Records
Message record formats from the TDX packet queue are
unpacked and transferred to the Z80 SIO.
4.2) Record Unpack
The records from the TDX packet queue are tested for
certain control flags and defined characters are added.
4.3) Alphabet Converting
If enabled, ITA 5 characters will be converted to ITA
2.
4.4) Character Transfer to transmit character queue
Unpacked and converted characters will be temporarily
stored in the transmit character queue.
4.5) Character Transmit
When the transmit buffer in the Z80 SIO is empty, a
"transmit interrupt" will cause the next character
to be transferred from the transmit character queue.
5) Line Handling
Line handling deals with handling of modem lines and
with opening and closing of logical channels and V24
transmission lines.
5.1) Read Status
A status read determines the action to be taken.
5.2) Open Channel
When an open channel command has been received, then
the modem line status will be tested. If the modem
lines indicate ready, then subroutine calls are made
to open the logical channel. The SIO receive interrupt
will be enabled and the modem lines changed according
to the CCITT recommendations.
5.2.3) Start Outputter
A start outputter command will be sent to the standard
firmware when the first incoming characters are transferred
to the TDX packet queue.
5.2.5) Enable SIO Interrupt
The SIO transmit interrupt will be enabled when the
first data are transferred to the TDX packet queue
from the TDX bus.
5.3) Close Channel
A specific V24 line and the applicable logical channel
will be closed if one of two events occur:
a) V24 modem line change occurs.
b) Close channel command is received.
A channel is closed by subroutine calls to the standard
firmware.
A V24 line is closed by disabling the SIO transmit
/ receive interrupts and by changing the modem lines
according to the CCITT recommendationss.
5.3.3) Stop Outputter
A stop outputter command will be sent to the standard
firmware when the last icncoming characters are transferred
to the TDX packet queue.
5.3.5) Disable SIO Interrupt
The SIO transmit interrupt will be disabled when there
is no more data in the TDX packet queue.
5.5) Report to Host
The following channel and line errors will be reported
to the host via the command channel.
a) Buffer overrun in TDX packet queue.
b) Overrun in outgoing/ingoing character queue.
c) V24 line not ready by channel/line open command.
d) Modem line change: identifying V24 line not
ready.
Fig. 4.2.4.1.1-8 Line Handling Breakdown
Fig. 4.2.4.1.1-9 Open/Close Channel/Line Breakdown
6) Modem Change
A shift in the V24 modem lines is detected by the Z80
SIO. When a change arises, the status table is updated
and the line handler module enabled.
7) Character Error
If the Z80 SIO detects a parity, frame or overrun error,
a special error interrupt is generated. The error interrupt
will cause deletion of the garbled character and generation
of an error flag.
When an error flag is set, the record generating module
will terminate the present record and generate an error
record with an error code.
Fig. 4.2.4.1.1-9 Modem Change Breakdown
Fig. 4.2.4.1.1-10 Character Error Breakdown
4.2.4.2 F̲i̲r̲m̲w̲a̲r̲e̲ ̲S̲t̲r̲u̲c̲t̲u̲r̲e̲
The LTUX application firmware is divided into processes
scheduled by the operating system and interrupt driven
firmware.
Processes scheduled by the operating system:
Command interpreter
Line handler
Records to host
Records from host
Interrupt driven firmware:
Character transmitter
Character receiver
Character error handler
V24 modem change
The firmware structure for the different processes
and subroutines is shown on the following pages.
C̲o̲m̲m̲a̲n̲d̲ ̲I̲n̲t̲e̲r̲p̲r̲e̲t̲e̲r̲
The command interpreter process is able to receive
and implement the following commands:
a) RESTART
b) OPEN CHANNEL
c) CLOSE CHANNEL
d) STATUS REPORT
e) CANCEL OUTGOING CHANNEL
The Command Intepreter is divided into the following
modules:
C̲o̲m̲m̲a̲n̲d̲ ̲F̲e̲t̲c̲h̲
The entry point is the COMFET module.
This module fetches the commands from the command channel
in the TDX packet queue. If no comments are available,
the scheduling routine is called.
C̲o̲m̲m̲a̲n̲d̲ ̲R̲e̲c̲o̲g̲n̲i̲z̲e̲
If the received command is recognized, one of the command
implementing modules is called, otherwise a completion
code is returned by the Command CC module.
Fig. 4.2.4.2.1-1 Command Interpret Firmware Structure
C̲o̲m̲m̲a̲n̲d̲ ̲C̲C̲ This module generates and sends a completion
code to the command originator.
L̲i̲n̲e̲ ̲H̲a̲n̲d̲l̲e̲r̲
The line handler process is enabled when one of the
following things occurs:
a) An open channel command is received.
b) A close channel command is received.
c) A modem change occurs.
The line handler is able to react on changes in the
V24 modem lines, according to CCITT recommendations.
DTE or DCE mode is selectable.
The Line Handler is divided into the following modules:
D̲e̲t̲e̲r̲m̲i̲n̲e̲ ̲A̲c̲t̲i̲o̲n̲
When the Line Handler is enabled, a flag in the status
register indicates the action to be taken.
U̲p̲d̲a̲t̲e̲ ̲S̲t̲a̲t̲u̲s̲
The status register is updated if any changeds have
occurred.
O̲p̲e̲n̲ ̲C̲h̲a̲n̲n̲e̲l̲
If the modem line status indicates ready and an open
channel command is received, then the specified channel
is opened, and the outgoing modem lines are changed
according to CCITT recommendations.
C̲l̲o̲s̲e̲ ̲C̲h̲a̲n̲n̲e̲l̲
If the modem line status indicates not ready, or if
a close channel command is received, then the specified
channel size is closed and the outgoing modem lines
are changed according to CCITT recommendations.
Fig.4.2.4.2.1-2 Line Handler Firmware Structure.
R̲e̲c̲o̲r̲d̲s̲ ̲t̲o̲ ̲H̲o̲s̲t̲
The Records to Host process is scheduled by the LTUX
operating system and is enabled at power up or restart.
Records to Host consist of the following modules:
G̲e̲t̲ ̲C̲h̲a̲r̲a̲c̲t̲e̲r̲
This is the process entry point.
Characters are fetched from the receive character queue
and if requested, they are converted to ITA 5.
A̲l̲p̲h̲a̲b̲e̲t̲ ̲C̲o̲n̲v̲e̲r̲t̲e̲r̲
The incoming characters are converted to ITA 5.
R̲e̲c̲o̲r̲d̲ ̲G̲e̲n̲e̲r̲a̲t̲e̲
The message record format is generated by this module.
The incoming characters are collected in a buffer.
Each character is checked for any match with defined
control characters and character sequences. The number
of collected characters in the record buffer is registered
in the character count.
If one of the following events occurs, the record is
terminated and transferred to the host:
a) Record count reaches maximum.
b) A defined control character is detected.
c) A defined control sequence is detected.
d) A time out occurs.
e) A character error is detected.
f) A modem line change is detected.
R̲e̲c̲o̲r̲d̲ ̲T̲r̲a̲n̲s̲f̲e̲r̲
A call to the Record Transfer module will cause a transfer
of the terminated record buffer to the outgoing TDX
full packet queue. An empty record buffer is then transferred
from the outgoing TDX empty packet queue to the character
collect area.
Fig. 4.2.4..2.1-3 Record to Host Firmware Structure
R̲e̲c̲o̲r̲d̲s̲ ̲f̲r̲o̲m̲ ̲H̲o̲s̲t̲
Records from the host are placed in the "ingoing" full
TDX packet queue.( Refer Q…0f…4…0e… figure 4.2.4.3.2-1)
The incoming records are unpacked and CR-CR-LF sequence
added if required.
The unpacked and converted records are transferred
to the transmit character queue.
The Record from Host process consists of the following
modules:
G̲e̲t̲ ̲R̲e̲c̲o̲r̲d̲
This module gets the message record from the ingoing
full TDX packet queue.
A̲l̲p̲h̲a̲b̲e̲t̲ ̲C̲o̲n̲v̲e̲r̲t̲e̲r̲
The unpacked characters are converted from ITA 5 to
ITA 2, if the converter is called.
C̲h̲a̲r̲a̲c̲t̲e̲r̲ ̲T̲r̲a̲n̲s̲f̲e̲r̲
Each character is transferred to the transmit character
queue.
Fig. 4.2.4.2.1-4 Records from Host Firmware Structure
5.0 C̲h̲a̲r̲a̲c̲t̲e̲r̲ ̲T̲r̲a̲n̲s̲m̲i̲t̲t̲e̲r̲
The transmitter is activated when the SIO buffer is
empty and a character from the transmit character queue
is transferred to the SIO buffer.
If the FIFO was empty, an empty flag would be set in
the status register.
6.0 C̲h̲a̲r̲a̲c̲t̲e̲r̲ ̲R̲e̲c̲e̲i̲v̲e̲r̲
The receiver is activated when the SIO receives a character.
The received character is transferred from the SIO
buffer to the receive character queue.
7.0 C̲h̲a̲r̲a̲c̲t̲e̲r̲ ̲E̲r̲r̲o̲r̲ ̲H̲a̲n̲d̲l̲e̲r̲
The error handler is activated when the SIO detects
a character error. A character error is frame error,
parity error or SIO buffer overrun error. The characters
involved will be deleted and an error flag set in the
status register.
8.0 V̲2̲4̲ ̲M̲o̲d̲e̲m̲ ̲C̲h̲a̲n̲g̲e̲
A change in the V24 modem lines, caused by external
equipment, activates the V24 Modem Change module. The
module status is updated and the Line Handler enabled.
4.2.4.3 D̲a̲t̲a̲ ̲F̲l̲o̲w̲ ̲a̲n̲d̲ ̲C̲o̲n̲t̲r̲o̲l̲ ̲L̲o̲g̲i̲c̲
4.2.4.3.1 D̲a̲t̲a̲ ̲F̲l̲o̲w̲
The data flow is presented in HIPO chart.
HIPO charts - 11 pages
4.2.4.3.2 C̲o̲n̲t̲r̲o̲l̲ ̲L̲o̲g̲i̲c̲
Explanation regarding fig. 4.2.4.3.2-1:
INT 1 - Incoming character interrupt from SIO.
INT 1 indicates that a character is ready
to be collected.
INT 2 - Character error interrupt from SIO.
INT 2 activates the Character Error module.
INT 3 - Modem change interrupt from SIO.
A change in the ingoing modem lines causes
INT 3.
INT 4 - Outgoing character interrupt from SIO.
INT 4 indicates that the outgoing SIO character
buffer is empty.
Q1 - Outgoing record queue.
Records containing data and control characters
are transported to Q1.
Q2 - Incoming command queue.
Commands from CR80D host are received in
Q2.
Q3 - Command response queue.
Command completion codes are returned to
the host in Q3.
Q4 - Incoming record queue.
Records containing data and control logic
are received from Q4.
F1 - Receive character queue.
Characters from the the Receiver are temporarily
stored in the incoming FIFO.
F2 - Transmit character queue.
Characters to the Transmitter are temporarily
stored in the outgoing file.
1 - When an open/close channel command is received,
the status register is updated and the
line handler enabled.
2, 3 - The command interpret module sets up the
buffer size when an open command is received.
4 - When a character error is received, the
garbled character is deleted, the present
record terminated and an error code record
generated.
5 - A modem change enables the Line Handler.
6, 7 - The Line Handler enables and disables the
Transmitter and Receiver.
Fig. 4.3.2.3.2-1 LTUX Control Logic
4.2.4.4 S̲u̲b̲-̲P̲a̲c̲k̲a̲g̲e̲ ̲D̲a̲t̲a̲
The data and control characters are transported between
the LTUX and TDX handlers in the Message Record Format.
The Message Record Format consists of a start byte
1E HEX, used as a record separator, a byte count that
gives the number of data bytes and a flag byte.
The flag byte identifies the type of data in the record.
F̲l̲a̲g̲ ̲B̲y̲t̲e̲ ̲V̲a̲l̲u̲e̲s̲
FLAG NO. DESCRIPTION LOW SPEED LINES LTUX
HOST
̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲
̲ ̲ ̲ ̲ ̲ ̲
0 Normal data Oversize line or premature
termination
1 Line or field where CR-CR-LF was detected
by
the LTUX
3 Special control character. Key on/off.
4 Control sequence.
9 End of sequence (normal or errored)
termination
HOST
LTUX
̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲
̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲
0 Normal data
1 Line or field where CR-CR-LF is added by
the
LTUX
4 Control sequence
FLAG NO. DESCRIPTION OCR LTUX
HOST
̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲
̲ ̲ ̲ ̲ ̲ ̲
0 Normal data. Oversize line or premature
terminator.
1 Line or field where CR-CR-LF or CR-LF was
detected by the LTUX
3 Control report
4 Control sequences
9 End of sequence ETB
HOST
LTUX
̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲
̲ ̲ ̲ ̲ ̲ ̲
4 Control sequences
FLAG NO. DESCRIPTION VDU LTUX TO
HOST
̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲
̲ ̲ ̲ ̲ ̲ ̲
0 Normal Data. Oversize line or premature
termination.
1 Line or field. Field separator 1C HEX.
3 Interrupt sequence. Control report.
4 Control sequence.
8 Start of sequence. STX separator.
9 End of sequence. ETX block control.
HOST
TO LTUX
̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲
̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲
0 Normal data.
1 Line or field. LTUX clear line, send data
and TAB
4 Control sequence.
8 Transmission protocol indicator.
9 Transmission protocol terminator.
4.2.4.5 S̲u̲b̲-̲P̲a̲c̲k̲a̲g̲e̲ ̲I̲n̲t̲e̲r̲f̲a̲c̲e̲
4.2.4.5.1 I̲n̲t̲e̲r̲f̲a̲c̲e̲ ̲t̲o̲ ̲L̲T̲U̲X̲ ̲H̲a̲n̲d̲l̲e̲r̲
The interface to the LTUX Handler is implemented by
means of command and completion codes sent via the
LTUX command channel.
The data interface is implemented with the Message
Record Format and the different flag types mentioned
in section 4.3.2.4.4.
The commands from the LTUX Handler are as follows:
COMMAND CODE COMMAND DESCRIPTION
̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲
̲ ̲ ̲ ̲ ̲ ̲
0 Restart LTUX. Same function as power
up initialize.
1, CH Open specified channel.
2, CH Close specified channel.
3, CH Status request.
4, CH Cancel specified outgoing channel.
In the command completion codes, the command is repeated
and a code identifies whether the command was executed
or not.
4.2.4.5.2 I̲n̲t̲e̲r̲f̲a̲c̲e̲ ̲t̲o̲ ̲S̲t̲a̲n̲d̲a̲r̲d̲ ̲F̲i̲r̲m̲w̲a̲r̲e̲
The interface between the LTUX application and the
standard firmware is implemented by means of a number
of sub-routine calls.
The sub-routines and their function will be described
in this chapter. For further details please refer to
CSD-MIC/220/PSP/0012.
O̲p̲e̲r̲a̲t̲i̲n̲g̲ ̲S̲y̲s̲t̲e̲m̲
The standard firmware includes a simple operating system.
This system will be used to schedule the application
firmware processes.
The operating system uses a standard schedule list,
which is not changeable.
It is possible to schedule up to 12 application processes.
The following sub-routine calls are available to control
the operating system:
C̲r̲e̲a̲t̲i̲n̲g̲ ̲R̲o̲u̲t̲i̲n̲e̲
This routine creates and activates a process.
Input parameters: Process number and Process start
address.
A̲c̲t̲i̲v̲a̲t̲i̲n̲g̲ ̲R̲o̲u̲t̲i̲n̲e̲
A specified process will be activated.
Input parameter: Process number.
P̲a̲s̲s̲i̲v̲a̲t̲i̲n̲g̲ ̲R̲o̲u̲t̲i̲n̲e̲
A specified process will be de-activated.
Input parameter: Process number.
S̲c̲h̲e̲d̲u̲l̲i̲n̲g̲ ̲R̲o̲u̲t̲i̲n̲e̲
When a process calls the scheduling routine, the CPU
stackpointer will be saved and the operating system
will switch to the next process in the schedule list.
To obtain maximum throughput, this routine must be
called by the running process with about 1 msec. intervals.
This is necessary, because the operating system is
not supplied with a time-out facility.
P̲a̲c̲k̲e̲t̲ ̲Q̲u̲e̲u̲e̲
The maximum number of logical channels is ten.
To each channel there are assigned four queue heads:
1) Outgoing empty queue head.
2) Outgoing full queue head.
3) Ingoing empty queue head.
4) Ingoing full queue head.
The queue heads are placed in the system RAM area.
The buffers belonging to the queue heads are created
by the buffer evaluating routine.
B̲u̲f̲f̲e̲r̲ ̲E̲v̲a̲l̲u̲a̲t̲i̲n̲g̲ ̲R̲o̲u̲t̲i̲n̲e̲
This routine creates a defined buffer for a specific
queue head.
Input parameters:
Offset - space between buffer head and buffer area.
Buffer size - this is the same as packet size.
Pointer to buffer head.
Pointer to queue head.
Output parameter:
Pointer to next buffer head.
C̲o̲m̲m̲a̲n̲d̲ ̲H̲a̲n̲d̲l̲e̲r̲
The LTUX application firmware is able to control the
standard firmware via different commands.
The commands are executed by calling the command handler
routine. The input parameters decide the command type.
C̲o̲m̲m̲a̲n̲d̲ ̲H̲a̲n̲d̲l̲e̲r̲ ̲R̲o̲u̲t̲i̲n̲e̲
Input parameters: Command type
Channel number
CR-ID
Timer adjustment.
Output parameters: Command acknowledge
CR-ID.
The following command types are applicable:
S̲t̲o̲p̲ ̲O̲u̲t̲p̲u̲t̲t̲e̲r̲
Stops packet transmit from defined channel.
S̲t̲a̲r̲t̲ ̲O̲u̲t̲p̲u̲t̲t̲e̲r̲
Starts packet transmit from defined channel.
S̲t̲o̲p̲ ̲I̲n̲p̲u̲t̲t̲e̲r̲
Stops packet receive to defined channel.
S̲t̲a̲r̲t̲ ̲I̲n̲p̲u̲t̲t̲e̲r̲
Starts packet receive to defined channel.
O̲p̲e̲n̲ ̲C̲h̲a̲n̲n̲e̲l̲
The CR-ID for a defined channel is inserted in the
protocol descriptor and the channel number is inserted
in the scan table.
C̲l̲o̲s̲e̲ ̲C̲h̲a̲n̲n̲e̲l̲
The channel number is removed from the scan table.
T̲e̲s̲t̲ ̲S̲c̲a̲n̲ ̲T̲a̲b̲l̲e̲ followed by R̲e̲q̲u̲e̲s̲t̲ ̲A̲n̲s̲w̲e̲r̲
If the specified channel is opened, then the CR-ID
is returned.
A̲d̲j̲u̲s̲t̲ ̲R̲e̲c̲e̲i̲v̲e̲ ̲T̲i̲m̲e̲r̲
The acceptable time from first to last frame in a packet
is set by this command.
A̲d̲j̲u̲s̲t̲ ̲T̲r̲a̲n̲s̲m̲i̲t̲ ̲T̲i̲m̲e̲r̲
The acceptable time delay from when first frame in
a packet is transmitted (to the packet ACK or NAK),
to when it is received. This timeout is for transmission
on the TDX bus.
I̲n̲p̲u̲t̲ ̲P̲e̲r̲m̲i̲t̲
This command informs the sending TDX device that a
defined channel is ready to accept data.
I̲n̲p̲u̲t̲ ̲N̲o̲t̲ ̲P̲e̲r̲m̲i̲t̲
The sending TDX device will be informed that a defined
channel cannot accept data.
A̲p̲p̲l̲i̲c̲a̲t̲i̲o̲n̲ ̲Q̲u̲e̲u̲e̲ ̲A̲c̲c̲e̲s̲s̲ ̲R̲o̲u̲t̲i̲n̲e̲
I̲G̲E̲P̲A̲ ̲R̲o̲u̲t̲i̲n̲e̲
Dequeue first buffer of ingoing full buffer queue head.
Input paramater: Channel number.
Output parameter: Queue status.
If full buffer, then find first
buffer
head address.
O̲D̲E̲P̲A̲ ̲R̲o̲u̲t̲i̲n̲e̲
Enqueue (i.e. put into queue) defined buffer of outgoing
full buffer queue head.
Input parameter: Channel number.
Buffer head address.
O̲G̲E̲P̲A̲ ̲R̲o̲u̲t̲i̲n̲e̲
Dequeue first buffer of outgoing empty buffer queue
head.
Input parameter: Channel number.
Output parameter: Queue status.
If empty buffer, then first buffer
head address.
I̲D̲E̲P̲A̲ ̲R̲o̲u̲t̲i̲n̲e̲
Enqueue defined buffer of ingoing empty buffer queue
head.
Input parameters: Channel number.
Buffer head address.
E̲n̲q̲u̲e̲u̲i̲n̲g̲ ̲R̲o̲u̲t̲i̲n̲e̲
Enqueue defined buffer in specified application created
queue head.
Input parameters: Queue head address.
Buffer head address.
D̲e̲q̲u̲e̲u̲i̲n̲g̲ ̲R̲o̲u̲t̲i̲n̲e̲
Dequeue first buffer in specified application created
queue head.
Input parameters: Queue head address.
Output parameters: Queue status.
If any buffer, then first buffer
head
address.
4.2.5 N̲I̲C̲S̲-̲T̲A̲R̲E̲ ̲L̲T̲U̲ ̲F̲u̲n̲c̲t̲i̲o̲n̲s̲ ̲S̲u̲b̲p̲a̲c̲k̲a̲g̲e̲
Refer appendix A.
4.2.6 C̲C̲I̲S̲/̲S̲C̲A̲R̲S̲ ̲L̲T̲U̲ ̲F̲u̲n̲c̲t̲i̲o̲n̲s̲ ̲S̲u̲b̲p̲a̲c̲k̲a̲g̲e̲
Refer Appendix B.
4.2.7 S̲S̲C̲ ̲I̲n̲t̲e̲r̲f̲a̲c̲e̲ ̲S̲u̲b̲p̲a̲c̲k̲a̲g̲e̲
4.2.7.1 F̲u̲n̲c̲t̲i̲o̲n̲ ̲S̲p̲e̲c̲i̲f̲i̲c̲a̲t̲i̲o̲n̲
The SSC Interface Subpackage provides the interface
to the watch dog or, in the event of a VDU being directly
connected to the PU, an alternative interface to the
VDU.
The SSC Interface Subpackage is a Handler in DVM sense,
replacing the standard OCH in the operational CAMPS
configurations.
The SSC Interface Subpackage implements a multiplexed
connection to the watchdog, alternatively, a VDU interface.
4.2.7.1.1 F̲u̲n̲c̲t̲i̲o̲n̲ ̲B̲r̲e̲a̲k̲d̲o̲w̲n̲
The functional breakdown is shown in figures 4.2.7.1.1-1
to 4.2.7.1.1-7.
Fig. 4.2.7.1.1-1
Fig. 4.2.7.1.1-2
Fig. 4.2.7.1.1-3
Fig. 4.2.7.1.1-4
Fig. 4.2.7.1.1-5
Fig. 4.2.7.1.1-6
Fig. 4.2.7.1.1-7
4.2.7.1.2 F̲u̲n̲c̲t̲i̲o̲n̲a̲l̲ ̲D̲e̲s̲c̲r̲i̲p̲t̲i̲o̲n̲
Handler functions are those required by DVM. They are
the following:
Initialize: Memory is prepared for channel command.
Shutdown: All operations are cancelled with no response
and channels closed.
Dismantle: Cancel all operations initiated by the
caller.
Error: Mark device in error.
Status: Return status.
Access: Test security profile.
Test: If V24 line free, issue test.
The handler functions include the capability of performing
operation with one external channel (and only one protocol)
or to run in a multiplexed mode with three channels.
Protocol functions. These are the interface functions
required by TMS.
The SSC Handler supports inclusion of three protocols:
1. VDU protocol. (As VDU handler section 4.2.2
with a record conversion).
2. Record Format protocol. This provides a formatting
from/to CAMPS internal format to/from format
in ITA 5.
3. Transparent protocol. This makes no transformation.
MAP interface funtions. The MAP interface may be initialized
to operate either in a single channel or a triple channel
configuration. When operating as a single channel,
no additional characters are transmitted . When operating
as a triple channel, blocks of data with channel number
are transmitted.
4.2.7.2 S̲o̲f̲t̲w̲a̲r̲e̲ ̲S̲p̲e̲c̲i̲f̲i̲c̲a̲t̲i̲o̲n̲
The SSC Handler has three entry points.
Enter-handler - p (requests via DVM):
Depending on the function requested, it turns to one
of the DVM functions or the TMS protocol function for
the appropriate channel.
Enter-Handler - h (handler - handler calls):
This entry must exist but is illegal.
Enter-handler - notification:
This entry is invoked by firmware when an MAP V24 notification
of output or input is present. Depending on the initiator,
either input or output routine is invoked.
4.2.7.3 D̲a̲t̲a̲ ̲F̲l̲o̲w̲ ̲a̲n̲d̲ ̲C̲o̲n̲t̲r̲o̲l̲ ̲L̲o̲g̲i̲c̲
Depending on the initialization of the SSC handler,
it may operate in one of two modes, the watchdog mode
or the non watchdog mode.
4.2.7.3.1 W̲a̲t̲c̲h̲d̲o̲g̲ ̲M̲o̲d̲e̲ ̲F̲l̲o̲w̲
Fig. 4.2.7.3.1-1 gives a presentation and the following
pages the control.
Fig. 4.2.7.3.1-1 Watchdog Mode Flow Overview
ENTER-HANDLER - P
HANDLER FUNCTION PROCESS FUNCTION
(PROTOCOL FUNCTION)
CHANNEL NOT CREATED RETURN ERROR
CH1? REQ. ENTRY CH1
CH2? REQ. ENTRY CH2
(CH3)
REQ. ENTRY CH3
ENTER-HANDLER - H
PUT ERROR
ENTER-HANDLER - NOTIFICATION
NO PENDING REQUEST IGNORE
INPUT
ACK UNDER
RECEPTION
ACK NOT
COMPLETE
START OF ACK
PROTOCOL ENTRY
ANSWER
INPUT NOT
COMPLETE
PROTOCOL
ENTRY ANSWER
FLAG PENDING
ACK TRANSMISSION
(OUTPUT)
ACK IN TRANSMISSION
ACK NOT COMPLETE - SEND NEXT
DATA
SELECT NEXT TRANSMISSION
NONE
SEND NEXT
The protocol flow is as follows:
Fig. 4.2.7.3.1-2 gives VDU protocol flow.
The flow is as specified for the VDU handler (refer
section 4.2.2) with the format conversion and VDU data
transfer protocol as described in LTUX functions subpackage
(section 4.2.4).
Fig. 4.2.7.3.1-2 VDU Protocol
Fig. 4.2.7.3.1-3 gives the Record Format Protocol.
The conversion is for record types 0, 1 and 4 as described
in the LTUX Functions Subpackage.
Fig. 4.2.7.3.1-4 gives the Transparent Protocol.
Fig. 4.2.7.3.1-3 Record Format Protocol
Fig. 4.2.7.3.1-4 Transparent Protocol
4.2.7.3.2 N̲o̲n̲-̲W̲a̲t̲c̲h̲d̲o̲g̲ ̲M̲o̲d̲e̲ ̲F̲l̲o̲w̲
The flow in the Non-Watchdog Mode is similar to the
flow in Watchdog Mode except that only one protocol
is allowed. (Only one channel may be created).
4.2.7.4 S̲u̲b̲p̲a̲c̲k̲a̲g̲e̲ ̲D̲a̲t̲a̲
The subpackage data includes the following:
Channel Control Blocks
Protocol Control Data
Pending Transfer Control Block and
Data Buffers for Protocols.
MAP interface data supporting 2 reads and 3 writes
per channel.
4.2.7.5 S̲u̲b̲p̲a̲c̲k̲a̲g̲e̲ ̲I̲n̲t̲e̲r̲f̲a̲c̲e̲s̲
The application interface for the SSC subpackage is
as described for the protocol in section 4.1.6.
For the Watchdog interface / normal V24 interface it
is shown in figure 4.2.7.5. The actual data transferred
depends on the protocol used.
Fig. 4.2.7.5 MAP V24 Interface Data
4.2.8 P̲U̲-̲P̲U̲ ̲H̲a̲n̲d̲l̲e̲r̲ ̲S̲u̲b̲p̲a̲c̲k̲a̲g̲e̲
4.2.8.1 F̲u̲n̲c̲t̲i̲o̲n̲a̲l̲ ̲S̲p̲e̲c̲i̲f̲i̲c̲a̲t̲i̲o̲n̲
4.2.8.1.1 F̲u̲n̲c̲t̲i̲o̲n̲a̲l̲ ̲B̲r̲e̲a̲k̲d̲o̲w̲n̲
The PU-PU handler implements the definition of terminals
in DAMOS TMS sense for the PU-PU TDX interface. Besides
that, the PU-PU handler provides a transparent data
transport interface.
Fig. 4.2.8.1-1 presents the functional breakdown.
Fig. 4.2.8.1-1
4.2.8.1.2 F̲u̲n̲c̲t̲i̲o̲n̲a̲l̲ ̲D̲e̲s̲c̲r̲i̲p̲t̲i̲o̲n̲
The initialization is to reserve memory for buffers
and transfer control blocks.
Channel Control is channel oriented control commands
including definition of terminal. The PU-PU connection
is seen as one terminal in TMS sense.
Terminal control is creation and deletion of terminal.
Data transfer functions are input and output with intermediate
storage. As the data transfer load for output and input
may be very different, the number of buffers and the
buffer size for output and input are configurable parameters.
As an example, the Active P.U. will mainly send checkpoint
information whereas the standby mainly receives. If
the PU-PU handler is to be used in both configurations
based on the same initialization, it should of course
be configured to input and output.
4.2.8.2 S̲o̲f̲t̲w̲a̲r̲e̲ ̲S̲p̲e̲c̲i̲f̲i̲c̲a̲t̲i̲o̲n̲
The PU-PU handler has two entry points, one for TMS
requests and one for TDX responses received.
Fig. 4.2.8.2-1 presents.
Fig. 4.2.8.2-1
4.2.8.3 D̲a̲t̲a̲ ̲F̲l̲o̲w̲ ̲a̲n̲d̲ ̲C̲o̲n̲t̲r̲o̲l̲ ̲L̲o̲g̲i̲c̲
The Handlers input and output transfer is performed
using two buffers. Refer fig. 4.2.8.3.
For output, the TMS requests a buffer, fills it and
returns it to the handler. The handler requests the
TDX to perform the transfer and upon completion (TDX
Response Entry) the buffer is made available for continued
transfer.
As the handler should be able to process up to several
thousand bytes per second, two output buffers are defined,
the length configurable.
For input, the Handler uses two buffers as well. For
each free buffer, the Handler has a pending input request
to the TDX. Whenever a buffer is filled and the TMS
has requested input, it is asyncroneously returned
to the TMS. Whenever TMS requests input and data is
already available, the buffer is immediately returned.
Fig. 4.2.8.3 PU-PU Handler Data Flow
4.2.8.4 S̲u̲b̲p̲a̲c̲k̲a̲g̲e̲ ̲D̲a̲t̲a̲
The PU-PU handler has for output:
2 buffers
3 PTCBs (Pending transfer control blocks)
and for input:
2 buffers
3 PTCBs (Pending transfer control blocks).
For control:
One buffer for reception of control command, return
of control info and one PTCB for pending control transfer.
4.2.8.5 S̲u̲b̲p̲a̲c̲k̲a̲g̲e̲ ̲I̲n̲t̲e̲r̲f̲a̲c̲e̲s̲
The PU-PU handler interface is as described in section
4.1.6.2.2.5 a transparent data interface.
4.3 M̲e̲m̲o̲r̲y̲ ̲L̲a̲y̲o̲u̲t̲
4.3.1 F̲o̲r̲m̲a̲t̲ ̲H̲a̲n̲d̲l̲e̲r̲ ̲M̲e̲m̲o̲r̲y̲ ̲L̲a̲y̲o̲u̲t̲
The Format Handler is a set of monitor procedures running
under control of the calling processes. In each of
the calling processes, the Format Handler has a work
area as described in section 4.2.1. Figure 4.3.1-1
gives the layout.
The program is common for all processes and it has
a size of 3 kWords. The address of the process-local
Format Handler data is placed on a fixed logical address
(known to the program).
Fig. 4.3.1-1
4.3.2 L̲T̲U̲X̲ ̲H̲a̲n̲d̲l̲e̲r̲ ̲M̲e̲m̲o̲r̲y̲ ̲L̲a̲y̲o̲u̲t̲
The LTUX handler is a set of protocol procedures accessed
for various channels. For each channel, a data area
is laid out corresponding to the type of protocol.
The VDU Handler program size is 2.5 kWords. The OCR
Handler program size is 1.5 kWords The Low Speed Line
Handler program size i 1 kWords.
Fig. 4.3.2-1 presents the memory layout.
Fig. 4.3.2-1
4.3.3 L̲T̲U̲ ̲H̲a̲n̲d̲l̲e̲r̲ ̲M̲e̲m̲o̲r̲y̲ ̲L̲a̲y̲o̲u̲t̲
The LTU Handler is a set of protocol routines accessed
for NICS-TARE or CCIS/SCARS channels. For each channel
a data area is laid out corresponding to the type of
protocol.
The NICS-TARE Handler program size is 3.5 kWords.
The CCIS/SCARS Handler program size is 3 kWords.
Fig. 4.3.3-1 presents the memory layout.
Fig. 4.3.3-1
4.3.4 L̲T̲U̲X̲ ̲F̲u̲n̲c̲t̲i̲o̲n̲ ̲S̲u̲b̲p̲a̲c̲k̲a̲g̲e̲ ̲M̲e̲m̲o̲r̲y̲ ̲L̲a̲y̲o̲u̲t̲
The LTUX protocol firmware is all integrated in one
LTUX.
Program Size: 4 kBytes
Data Size: max. 3 kBytes.
4.3.5 N̲I̲C̲S̲-̲T̲A̲R̲E̲ ̲F̲u̲n̲c̲t̲i̲o̲n̲ ̲S̲u̲b̲p̲a̲c̲k̲a̲g̲e̲ ̲M̲e̲m̲o̲r̲y̲ ̲L̲a̲y̲o̲u̲t̲
Refer Appendix A.
4.3.6 C̲C̲I̲S̲/̲S̲C̲A̲R̲S̲ ̲L̲T̲U̲ ̲F̲u̲n̲c̲t̲i̲o̲n̲s̲ ̲S̲u̲b̲p̲a̲c̲k̲a̲g̲e̲ ̲M̲e̲m̲o̲r̲y̲ ̲l̲a̲y̲o̲u̲t̲
Refer Appendix B.
4.3.7 S̲S̲C̲ ̲I̲n̲t̲e̲r̲f̲a̲c̲e̲ ̲S̲u̲b̲p̲a̲c̲k̲a̲g̲e̲ ̲M̲e̲m̲o̲r̲y̲ ̲L̲a̲y̲o̲u̲t̲
The SSC Interface Subpackage consists of a handler
for the MAP V24 interface plus a set of protocol routines,
namely:
VDU Handler
Record Format Handler
Transparent Protocol Handler.
The Memory Layout is shown in fig. 4.3.7-1
Fig. 4.3.7-1
4.3.8 P̲U̲-̲P̲U̲ ̲H̲a̲n̲d̲l̲e̲r̲ ̲M̲e̲m̲o̲r̲y̲ ̲L̲a̲y̲o̲u̲t̲
The PU-PU Handler implements the following:
A transparent protocol.
Memory Layout.
1 k program and a data buffer.
