Jason Foo was conversing with All about Zmodem upload trouble.

 JF> The weirdest thing is, downloading works perfectly, and I get an
 JF> average CPS rate of 1650-1700 bps (it's a 14400 modem).

By the sounds of it, you've got your flow control set wrong.  Your modem is
downloading fine because you've probably got your port speed locked on
19200.  Being faster than the modem speed, it copes happily with your
downloads.  When you upload, you are sending information to the modem at
19200, but it is only being sent from the modem at 14400.  Therefore, your
buffer will be overflowing because it can't tell the computer to stop
sending momentarily and information is getting lost.

If you have a 7 wire (or more) serial cable, set your comm program to use
RTS/CTS flow control (also known as handshaking) and set the modem with the
command: AT&K3.  This will set your system to use hardware handshaking.  A
separate set of wires in the cable will be used.

If your cable is only 3 wire, you should get something better.  But until
then, set your comm program to X-On/X-Off flow control and set your modem
with the command: AT&K5.  This will send software commands between the
modem and computer using the normal transmission wires.

---

 * Kris Roebuck.

einstein{at}albanyis.com.au	or	kris.roebuck{at}mikesbbs.omen.com.au

 * AmyBW v2.11 *
... Howard is to the people of Australia what Microsoft is to software.

--- AmyBW v2.11