🚀 go-pugleaf

Karen Stratton <stratton@btg.com> wrote:

>I have a HP 715 running 9.05 and a PPI PM228MT II V.34 modem.  I am using a

>28800 modem.  But when I download files, my transfer rate is between 5-175
>bytes, yes I mean bytes, per second.

Try to tell the modem to ignore the RTS signal from the computer.
HP's and modern modems have different ideas of what RTS is going
to signal. 

While the old RS 232 standard (from the times when nobody thought a
serial device could be fast enough to overrun the computer
with data) says RTS is raised by the computer to signal the
external device "I'm about to send you data" (which was sensible
in those times because the modems had to turn on their modulator,
first, before they could accept data from the computer), most
modern serial hardware uses RTS as the counterpart to CTS,
making a bi-directional hardware-handshake possible: The computer
sets RTS to say "I'm ready to receive data" and the external serial
device sets CTS to say "I'm ready to receive data".

HP-UX assigns the "old" meaning to RTS, so a bidirectional 
hardware-hanshake isn't possible, only the data direction
HP->external is "safe".

BTW: USR Courier modems still allow one to choose between both
RTS-interpretations.

cu, Lutz Vieweg

Lutz Vieweg (lkv@mania.robin.de) wrote:
> Karen Stratton <stratton@btg.com> wrote:

> >I have a HP 715 running 9.05 and a PPI PM228MT II V.34 modem.  I am using a

> >28800 modem.  But when I download files, my transfer rate is between 5-175
> >bytes, yes I mean bytes, per second.

> Try to tell the modem to ignore the RTS signal from the computer.
> HP's and modern modems have different ideas of what RTS is going
> to signal. 

I am getting high speed in both directions on my HP-UX workstation, and I
do use RTS/CTS handshaking between the modem and my workstation.  The key
is setting up the device file on the workstation to use RTS/CTS flow
control.  The method of doing this is described in the Dependencies section
of the termio(7) man page.  There is one bit you can set to enable RTS/CTS
by default, and some other bits you can set to control the 16550 UART FIFO
trigger levels.

For instance, you might want to have the minor number of the device file
look like: 0x2040a9 for a dial-out device or 0x2040a8 for a dial-in device.
I don't know if SAM lets you tweak all of those bits in the minor device
number, but you can always use the mknod(1m) command to re-create the
device file.  Do an ls -l on the device file, and if the least significant
hex digit of the minor number is not 8 or 9, this is probably your problem.

--
Peter Notess			Hewlett-Packard Company
email: pcn@fc.hp.com		Network and System Management Div.
phone: (970) 229-3459		Fort Collins, CO