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Before this thread wanders COMPLETELY off-topic, I'll throw in my favorite company name: PMMI. They made 110 baud modem cards for S-100 computers (the pre-cursor to the PC). PMMI stood for "Potomac Micro Magic Incorporated." And back then, it really was magic... that's how I hooked up to Ward and Randy's CBBS. Joe I did a little digging, and found Ward's original MODEM program. Here is the read loop, with the timeout set to 100ms. Note that 100ms was just 1250 loops (2500 for a FAST processor). ;THIS SUBROUTINE WILL LOOP UNTIL THE MODEM RECEIVES A CHARACTER ;OR 100 MILLISECONDS. IF A CHARACTER IS RECEIVED, A FLAG IS SET ;TO STORE THE CHARACTER. A MAXIMUM OF TWO CHARACTERS ARE STORED, ;BUT MORE MAY BE STORED IF DESIRED (SEE COMMENT IN "INTDSKSV" ;ABOVE). INMODEM: LDA FASTCLK ORA A JZ SLOW LXI B,2500 JMP TIMERL SLOW: LXI B,1250 TIMERL: CALL IN$MODlsr CALL ANI$MODRCVB CALL CPI$MODRCVR JZ GETBYTE DCX B MOV A,B ORA C JNZ TIMERL RET > From: James H H Lampert > > Incidentally, my old Tandy 1000SL had an EMS card made by a company called > "Micro-Mainframe."
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