terry@wsccs.UUCP (terry) (02/28/88)
In article <216@mccc.UUCP>, pjh@mccc.UUCP (Peter J. Holsberg) writes: > In article <231@stcns3.stc.oz> dave@stcns3.stc.oz (Dave Horsfall) writes: > |Anyone tried the 'Blazers on protocols other than UU**? > > I've used one with a hayes 2400 and zmodem protocol, and consistently > get 235+ cps. But that's probably not what you're asking, right? I don't think that's what he's asking, either. If you mean 'Xmodem', 'Kermit', 'TERM', or something else useful, you have to turn off flow control 1) modem to modem, and 2) modem to computer, on both ends to avoid it 'sticking' when it sees a ^S. On any protocol, you will probably have to tweak the sender and receiver timeouts to avoid the data being timed out while waiting for a Trail Blazer packeted packeted ACK. (not, that was not a mistake). This is easy on Kermit or TERM, impossible with xmodem... use relaxed xmodem. Say I am xferring a file to a remote system with xmodem, and, by some ungodly incredible stroke of luck, I manage to avoid sending any binary characters in the CRC or block-check (depending on version) fields. Suppose also that I get to packet 17... quick, what will the sequence # field contain? A control-Q (packet 19 is a ^S). The transfer blows out consistantly on large files (larger than approx 128*17 bytes, minus overhead). This is assuming I am sending a text file. If it is binary, it could strike any time. In addition, programs which auto-select CRC or Xmodem by which NAK they get back at first (C or ^U) may pick the wrong one if the modem gives them a ^Q or ^S when they send the first packet (hmmm... not a 'C'... must be checksum...). This is *not* only a problem with Trail Blazers. Any 2400 baud or above modem with flow control should have it turned off (my apologies to the people who thought locking the baud at 9600 was a good idea on a Microcom modem... you'll just have to send breaks to login like the rest of us). The worst offenders are modems with a single (*GASP*) ASCII character (without timing requirements on either side of it) to go back to command mode. You just can't send one.