[comp.dcom.modems] Telebit Trailblazer + and A/UX

root@radar.UUCP (root) (01/06/89)

Has anyone used a Telebit Trailblazer Plus modem with a Mac II under
A/UX?  I'm curious about what arrangements were used for flow control,
how it worked communicating with the Mac at 19.2K, and what kind of
throughput with uucp communicating with another TB+ was obtained.

pst@comdesign.CDI.COM (Paul Traina) (01/06/89)

From article <150@radar.UUCP>, by root@radar.UUCP (root):
> Has anyone used a Telebit Trailblazer Plus modem with a Mac II under
> A/UX?  I'm curious about what arrangements were used for flow control,
> how it worked communicating with the Mac at 19.2K, and what kind of
> throughput with uucp communicating with another TB+ was obtained.

I just set one up yesterday.  No flow control (actually, one *could*
use hardware flow control, since standard modem cables for the mac
have input-handshake going to pin 5 (cts) on a DB25, but then you
have no way of detecting carrier).  uucico seems to be configurable
to only 9600 baud.  I made a cursory stab at trying to get it to run
19.2k, but had no immediate success, so I just dropped in in at 9600.

Mac II <-> Sun 3/280 --- about 890 characters/sec (limited because of 9600
baud on the Mac...sigh).

For reference, IBM AT clone, Microport UNIX, 19.2k <-> Sun 3/280
runs on average about 14kbps, with occasional increases to 18k when
sending text (as opposed to compressed news batches).

All in all the TB+ is wonderful, the Mac leaves something to be desired.
I'm upset with apple that they do not provide more handshake lines.
Hardware flow control is the optimal way to deal with a modem, but
the mac only has one output signal (going to DTR) and one input
signal (going to CTS for a standard cable, DCD if you wish carrier
detect).

-- 
work:	pst@condor.cdi.com	{apple,pyramid,ucsbcsl,uunet}!comdesign!pst
play:	pst@ai.ai.mit.edu	{ucsbcsl,comdesign,dscvax2}!nessus!pst
school:	pst@cornu.ucsb.edu	pst@sbitp.bitnet
		"I'm not a scientist, but I play one on TV."

dag@fciva.FRANKLIN.COM (Daniel A. Graifer) (01/06/89)

In article <590@comdesign.CDI.COM> pst@comdesign.CDI.COM (Paul Traina) writes:
>From article <150@radar.UUCP>, by root@radar.UUCP (root):
>> Has anyone used a Telebit Trailblazer Plus modem with a Mac II under
>> A/UX? [...]
>I just set one up yesterday.  No flow control (actually, one *could*
>use hardware flow control, since standard modem cables for the mac
>have input-handshake going to pin 5 (cts) on a DB25, but then you
>have no way of detecting carrier).  [...]
>
>All in all the TB+ is wonderful, the Mac leaves something to be desired.
>I'm upset with apple that they do not provide more handshake lines.
>Hardware flow control is the optimal way to deal with a modem, but
>the mac only has one output signal (going to DTR) and one input
>signal (going to CTS for a standard cable, DCD if you wish carrier
>detect).
>
>-- 
>work:	pst@condor.cdi.com	{apple,pyramid,ucsbcsl,uunet}!comdesign!pst

The Prime EXL series ('386 MultiBusII box) has the same problem: only one
handshake line is provided in each direction.  They also use a non-standard
connector: an RJ45-10 (the Mac+, SE, & II use a MicrDIN-8 connector).

The according to the documentation, the early versions also didn't have a
Protective Ground line on their connectors.  The machine as shipped did, 
and the documentation caught up later.  In order to accommodate this, they
had to switch from an 8-pin to a 10-pin jack, but the board design was 
already locked in, with no separate allowance for DSR and DCD, so one pin
of the 10 is unused. 

In both cases, it seems that the manufacturers were looking for a connector 
that was:
	a) Familier to naive users (the MicroDIN-8 resembles an RCA phono
	   plug on a stereo, the RJ45-10 looks like a standard RJ45-8 business
	   telephone modular connector)
	b) A smaller plug to economize on back panal space.
In both cases, it appears that Marketing sense over-rode engineering sense.

	Ah, well....
	Dan

-- 
Daniel A. Graifer			Franklin Capital Investments
uunet!fciva!dag				7900 Westpark Drive, Suite A130
(703)821-3244				McLean, VA  22102

paul@taniwha.UUCP (Paul Campbell) (01/07/89)

In article <590@comdesign.CDI.COM> pst@comdesign.CDI.COM (Paul Traina) writes:
>From article <150@radar.UUCP>, by root@radar.UUCP (root):
>> Has anyone used a Telebit Trailblazer Plus modem with a Mac II under
>> A/UX?  I'm curious about what arrangements were used for flow control,
>> how it worked communicating with the Mac at 19.2K, and what kind of
>> throughput with uucp communicating with another TB+ was obtained.
>
>have no way of detecting carrier).  uucico seems to be configurable
>to only 9600 baud.  I made a cursory stab at trying to get it to run
>19.2k, but had no immediate success, so I just dropped in in at 9600.
>
>Mac II <-> Sun 3/280 --- about 890 characters/sec (limited because of 9600
>baud on the Mac...sigh).

I use a TB too I get 11kb average throughput when sending/receiving news
(the TB wont go much faster ...). I set it up for 19200 as below ....
(note I don't use the internal ports, I have an extra serial cardthat  'knows'
about the G protocol ... change the names/faces/devices to suit)


In L.sys I have:

fred Any,10 ttyc1 19200 ttyc1 "" \dA\dAT\r OK-AAAAT\r-OK \dATM0Q0V1S7=60S50=255S111=30\r OK ATDT111-1111\r CONNECT\sFAST "" in:-\r-in: Uxxxxxxx assword: xxxxxxx


In L-devices:

DIR	ttyc1	ttyc1	19200


	Paul

-- 
Paul Campbell			..!{unisoft|mtxinu}!taniwha!paul (415)420-8179
Taniwha Systems Design, Oakland CA

 	"Read my lips .... no GNU taxes"