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 ECOLOGY : FIELD TRIP TO CORREZE

CHECKING YOUR RAM MEMORY AND ARCHIVES

Checking Available Memory

MEMORY Menu
You can check available memory or manage existing memory by selecting items from the MEMORY menu. To access this menu, press then .

MEMORY
1:About... Displays information about the calculator.
2:Mem Mgmt/Del...Reports memory availability and variable usage.
3:Clear Entries Clears ENTRY (last-entry storage).
4:ClrAllLists Clears all lists in memory.
5:Archive... Archives a selected variable.
6:UnArchive... UnArchives a selected variable.
7:Reset... Displays the RAM, ARCHIVE, and ALL menus
8:Group... Displays GROUP and UNGROUP menus.

To check how much memory you have available, first press then and then 2:Mem Mgmt/Del.

To leave the MEMORY MANAGEMENT/DELETE menu, press either then or . Both options display the home screen.

Deleting Items from Memory

Deleting an Item

To increase available memory by deleting the contents of any variable(real or complex number, list, matrix, Y= variable, program, Apps, AppVars, picture, graph database, or string), follow these steps.

  1. Press then to display the MEMORY menu.
  2. Select 2:Mem Mgmt/Del to display the MEMORY MANAGEMENT/DELETE menu.
  3. Select the type of data you want to delete, or select 1:All for a list of all variables of all types. A screen is displayed listing each variable of the type you selected and the number of bytes each variable is using. For example, if you select 4:List, the LIST editor screen is displayed.

Press and to move the selection cursor (þ ) next to the item you want to delete, and then press DEL. The variable is deleted from memory. You can delete individual variables one by one from this screen.
To leave any variable screen without deleting anything, press then , which displays the home screen.

Note: If you are deleting programs or Apps, you will receive a message asking you to confirm this delete action. Select 2:Yes to continue.

Memory and CBL2 Data Collection

Three screens usually appear when there is not enough memory available in the calculator to collect any or all of the data and then graph it.

Check the RAM memory available.
Reduce the number of data points you are trying to collect or remove items from the memory.

The following are estimates of the number of data points that can be collected if the calculator RAM memory has been reset prior to sending DataMate to the calculator:

Calculator

1 sensor

2 sensors

TI-83

~200

~150

TI-83 Plus/89

998

~600

Note: If you use DataMate’s curve fit option uses more memory so less memory will be available for collecting data.

Archiving and UnArchiving Variables

  • Archiving allows you to store data, programs, or other variables to the user data archive where they cannot be edited or deleted inadvertently.
  • Archiving also allows you to free RAM for variables that may require additional memory.
  • Archived variables cannot be edited or executed. They can only be seen and unarchived. For example, if you archive list L1, you will see that L1 exists in memory but if you select it and paste the name L1 to the home screen, you won’t be able to see its contents or edit it.

Note: Not all variables may be archived. Not all archived variables may be unarchived. Apps and Groups always exist in Flash ROM so there is no need to archive them. Groups cannot be unarchived. However, you can ungroup or delete them.

Archiving and unarchiving can be done in two ways:

  • Use the 5:Archive or 6:UnArchive commands from the MEMORY menu or CATALOG.
  • Use a Memory Management editor screen.

Before archiving or unarchiving variables, particularly those with a large byte size (such as large programs) use the MEMORY menu to:

  • Find the size of the variable.
  • See if there is enough free space.

Note: If there is not enough space, unarchive or delete variables as necessary.

When you unarchive a variable, not all the memory associated with that variable in the archive will be made available since the system keeps track of where the variable has been and where it is now in RAM.

Even if there appears to be enough free space, you may see a Garbage Collection message when you attempt to archive a variable. Depending on the usability of empty blocks in the user data archive, you may need to unarchive existing variables to create more free space.

To archive or unarchive a list variable (L1) using a Memory Management editor:
  1. Press then to display the MEMORY menu.
  2. Select 2:Mem Mgmt/Del... to display the MEMORY MANAGEMENT/DELETE menu.
  3. Select 4:List... to display the LIST menu.
  4. Press to archive L1. An asterisk (*) will appear to the left of L1 to indicate it is an archived variable.
    To unarchive a variable in this screen, put the cursor next to the archived variable and press . The asterisk will disappear.
  5. Press then to leave the LIST menu.

Note: You can access an archived variable for the purpose of linking, deleting, or unarchiving it, but you cannot edit it.

Storing lists of data

Archiving data will remove it from the RAM memory but it will not stop it from being over-written when new data is recorded. It needs to be renamed.

To rename a list of data (e.g. L1)
  1. Select the list to be stored by pressing then then
  2. Open the LIST menu by pressing then and select OPS using the cursor
  3. Descend the menu using the cursor to B: L press and type in a code name for the list, it must start with a letter so press the green key and chose a letter.

Erasing a list of data
  1. Open the MEMORY menu by pressing then
  2. Select 2: Mem Mgmt/Del… then 4: List… and select the list to be erased by moving the cursor down the column. Erase the lists that you want using

© Paul Billiet 2004