Routines
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05918: THE 'STREAM DATA' SUBROUTINE
Used by the routines at CLOSE and OPEN.
This subroutine returns in the BC register pair the stream data for a given stream.
Output
BC Offset from the stream data table (STRMS)
HL Address of the offset in the stream data table
STR_DATA 05918 CALL FIND_INT1 The given stream number is taken off the calculator stack.
05921 CP 16 Give an error if the stream number is greater than 15.
05923 JR C,STR_DATA1
This entry point is used by the routines at OPEN and CAT_ETC.
Report O - Invalid stream.
REPORT_O_2 05925 RST 8 Call the error handling routine.
05926 DEFB 23
Continue with valid stream numbers.
STR_DATA1 05927 ADD A,3 Range now 3 to 18.
05929 RLCA And now 6 to 36.
05930 LD HL,23568 The base address of the stream data area.
05933 LD C,A Move the stream code to the BC register pair.
05934 LD B,0
05936 ADD HL,BC Index into the data area and fetch the the two data bytes into the BC register pair.
05937 LD C,(HL)
05938 INC HL
05939 LD B,(HL)
05940 DEC HL Make the pointer address the first of the data bytes before returning.
05941 RET
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