Operator`s manual

SECTION 4. EXTERNAL STORAGE PERIPHERALS
4-2
Only one of the options 1x, 2x, or 30 may be
used in a program. If using a SM64 Storage
Module, output code 21 should be used. Use of
the SM192/716 is discussed further in Section
4.4, print output formats are discussed in
Section 4.5.
Section 4.3 contains specifics on the cassette
recorder. Note that tape operation is for above
freezing temperatures only.
4.1.2 *4 MODE
The *4 Mode may be used in place of Instruction
96 to enable or disable printer and/or cassette
tape output and to set the printer baud rate. The
first parameter is a two digit number determining
the tape and printer status. The second is the
baud rate code. To enter a different status, key
in the appropriate code from Table 4.1-2,
followed by "A". Printer data is sent in the
printable ASCII format only (Section 4.5). If
tape or printer status is changed during
execution of the program tables, execution stops
until the programs are recompiled. Instruction
96 should be used to send data to the
SM192/716 Storage Modules. Do not use *4 if
Instruction 96 is used in the program.
TABLE 4.1-2. *4 Mode Parameters and
Codes
Display
Key ID:DATA Description
*4 04:00
A 01:XX Output Enable Code
(e.g., "10" means tape
enabled, printer disabled)
A 02:XX Baud Rate Code
Output Enable Codes
Code Description
X0 printer disabled
X1 printer enabled, ASCII
0X tape disabled
1X tape enabled
Baud Rate Codes
Code Baud Rate
00 300
01 1200
02 9600
03 76,800
4.2 MANUALLY INITIATED DATA
OUTPUT - *8 AND *9 MODES
Data may be transferred to tape using the *8
Mode and to printer or Storage Module using the
*9 Mode. These Modes allow the user to
retrieve a specific block of data, on demand,
regardless of whether or not the 21X is
programmed for on-line data output.
If external storage peripherals (cassette,
Storage Module, etc.) are not left on-line, the
maximum allowable time between visiting the
site to retrieve data must be calculated to insure
that data placed in Final Storage are not written
over before they are collected. In order to make
this calculation, users must determine: (1) the
size of Final Storage, (2) the number of output
arrays being generated, (3) the number of low
and/or high resolution data points included in
each output array, and (4) the rate at which
output arrays are stored in Final Storage. When
calculating the number of data points per output
array, remember to add 1 overhead data point
(2 bytes) per array for the output array ID.
For example, assume that 19,296 locations are
assigned to Final Storage (*A Mode), and that 1
output array, containing the Array ID (1 memory
location), 9 low resolution data points (9 memory
locations) and 5 high resolution data points (10
memory locations) is stored each hour. In
addition, an output array with the Array ID and 5
high resolution data points (11 memory
locations) is stored daily. This is a total of 491
memory locations per day ((20 x 24) + 11).
19,296 divided by 491 = 39.3 days. Therefore,
the 21X would have to be visited every 39 days
to retrieve data, because write-over would begin
in the 40th day.
4.2.1 MANUAL TAPE DUMP *8 MODE
If on-line tape storage is enabled, entering the *8
Mode will suspend it. If left in the *8 Mode, on-
line storage will be re-enabled if no key entries
are made for 3.4 minutes. Setting up the tape
recorder is discussed in Section 4.3.4.