Atari ST series Technical Reference Manual page 220

Output Graphics Screen to Printer
Scrdmp()
T h e S c r d m p ( ) f u n c t i o n p r i n t s a g r a p h i c r e p r e s e n t a t i o n o f t h e s c r e e n d i s ­
p l a y o n a n A t a r i o r E p s o n - c o m p a t i b l e p r i n t e r .
C macro format
S c r d m p ( );
Machine language format
m o v e . w # 2 0 , - ( s p )
tr a p # 1 4
a d d q .l # 2 , s p
Inputs
N o n e
Results
N o n e
See also
P r t b l k ( )
212
Scrdmp
Opcode = 20