srowe wrote:There's no difference in the number of calls but there is a difference in the number of cycles. To reach FACPTR from CHRIN takes 28 cycles, from ACPTR it takes 3. That's for each byte received.
ACPTR, CIOUT, LISTEN, SECOND, TALK, TKSA, UNLSN and UNTLK only work on the serial bus, only with the standard IEC protocol, and they are not vectored.chysn wrote:This poses an interesting philosophical question, because we all face questions about what level of abstraction we want to work at.
Using those calls instead of SETNAM, SETLFS, OPEN, CLOSE, CHKIN, CHKOUT, CHRIN, CHROUT and CLRCHN ties a program to that exact protocol and robs it of any chance to work with a faster implementation of the serial protocol (JiffyDOS or SJLOAD), or with IEEE-488 cards, or with an altogether different implementation of a CBM DOS-like device driver like Kananga's FE3 RAM Disk.
All that in the name of a few cycles saved per transmitted byte? Really?