Programming in iS-DOS

Greetings, O venerable All! Here is the PANEL procedure for working with file panels. Did I do everything right here? Maybe there's something missing? Or maybe something did you write too much? ;) PANEL LD IX,STOR_S; 4 bytes LD C,#37; restore the environment ;why is this needed, and in what cases? XOR A RST #10 RET C JR PANEL1 CH_DEV LD C,#02; _does this need to be done here_? RST #10 RET C ;device selection LD C,#8A RST #10 EXX LD A,#07 SUB B LD C,#8E RST #10 RET C CP#F1 JR NZ,PANELW PANEL1 LD A,#F0 LD C,#8E RST #10 RET C PANELW LD A,#FF LD C,#8E RST #10 RET C CP#08 JR C,CH_DEV; CS+1, CS+2, CS+3, CS+4 pressed CP#10 SCF RET Z; "SS+A" (failure) CP#0D JR NZ,PANELW LD C,#8A RST #10 LD C,#26 RST #10 RET C EXX PUSH HL LD BC,#000B ADD HL,BC BIT 5,(HL) POP HL RET Z; this is a file! LD A,#0D; open directory. LD C,#8E RST #10 JR NC,PANEL1 RET STOR_S DEFS 4 P.S. Maybe someone has a _complete_ description of restarts and others docks for version iS-DOS 3.5 and higher? And also a description of AS2.COM from 07.12.94. Best regards, Felix!