throughput using CTS flow control on a Trailblazer+

[Chuck Forsberg WA7KGX]

In article <871 at spdcc.COM> dyer at spdcc.COM (Steve Dyer) writes:
:I'm using a Telebit Trailblazer+ on one of my dialin ports, fixed at 19.2kb
:using hardware flow control (gettydefs has EXTA and CTSFLOW defined).  I'm
:finding that effective UUCP throughput ranges between 80-100 bytes per second
:when a UUCP neighbor without a Trailblazer dials in at 2400 baud, completely
:negating any benefit of the neighbor's >1200 baud speed.  The CTS light seems
:to blink on every SD (send data) blink.  People who dial in to this line at
:2400 baud also report jerkiness (although this seems to be hidden and not
:observable at 1200 baud.)
:
:Note we don't appear to be losing data; the low transfer rate isn't due to
:retransmissions, but due to (excessive?) throttling of the output stream.
:
TeleGodzilla uses a TrailBlazer (not plus) with the current software ROMS.
For a brief period of time I had TeleGodzilla switch to 19200 bps and
enable flow control when an MNP connection was established at 1200 or
2400 bps.  This had the same disappointing results as Steve has seen
with uucp.

Moral: With the current TB ROMS, It's OK to use flow control with PEP
but not MNP.  A bit of a problem for UUCP, unless it's front ended
with Pro-YAM.


Chuck Forsberg WA7KGX          ...!tektronix!reed!omen!caf 
Author of YMODEM, ZMODEM, Professional-YAM, ZCOMM, and DSZ
  Omen Technology Inc    "The High Reliability Software"
17505-V NW Sauvie IS RD   Portland OR 97231   503-621-3406
TeleGodzilla BBS: 621-3746   CIS: 70007,2304    Genie: CAF