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The address of this routine is found in the parameter table.
This command allows the user to OPEN streams. A channel code must be supplied and it must be 'K', 'k', 'S', 's', 'P', or 'p'.
Note that no attempt is made to give streams 0 to 3 their initial data.
OPEN 05942 RST 40 Use the calculator to exchange the stream number and the channel code.
05943 DEFB 1 exchange
05944 DEFB 56 end_calc
05945 CALL STR_DATA Fetch the data for the stream.
05948 LD A,B Jump forward if both bytes of the data are zero, i.e. the stream was in a closed state.
05949 OR C
05950 JR Z,OPEN_1
05952 EX DE,HL Save HL.
05953 LD HL,(23631) Fetch CHANS - the base address of the channel information and find the code of the channel associated with the stream being OPENed.
05956 ADD HL,BC
05957 INC HL
05958 INC HL
05959 INC HL
05960 LD A,(HL)
05961 EX DE,HL Return HL.
05962 CP "K" The code fetched from the channel information area must be 'K', 'S' or 'P'; give an error if it is not.
05964 JR Z,OPEN_1
05966 CP "S"
05968 JR Z,OPEN_1
05970 CP "P"
05972 JR NZ,REPORT_O_2
OPEN_1 05974 CALL OPEN_2 Collect the appropriate data in DE.
05977 LD (HL),E Enter the data into the two bytes in the stream information area.
05978 INC HL
05979 LD (HL),D
05980 RET Finally return.
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