Commodore 128 System Manual page 319

SPRSAV
Store sprite data from a text string variable into a sprite storage
area or vice versa
SPRSAV origin,destination
This command transfers a sprite image from a string variable to a
sprite storage area. It can also transfer the data from the sprite
storage area into a string variable. Either the origin or the
destination can be a sprite number or a string variable but they
both cannot be string variables. If you are moving a string into a
sprite, only the first 63 bytes of data are used. The rest are
ignored since a sprite can only hold 63 data bytes.
EXAMPLES:
SPRSAV 1,A$
Transfers the image pattern from sprite 1 to the string named A$.
SPRSAV B$,2
Transfers the data from string variable B$ into sprite 2.
SPRSAV 2,3
Transfers the data from sprite 2 to sprite 3.
NOTE: SPRSAV sprite, string produces a string in the same
format as SSHAPE so that it can be used with GSHAPE to 'fix' a
sprite onto a hi-res screen. The string will be 67 characters long.
S S H A PE /G SH A P E
Save/retrieve shapes to/from string variables
SSHAPE and GSHAPE are used to save and load rectangular
areas of multicolor or bit mapped screens to/from BASIC string
variables. The command to save an area of the screen into a
string variable is:
SSHAPE string variable, X1, Y1 [,X2,Y2]
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