Need pinouts!!!

[Scott J. Kleper]

I need a "map" of the pins for the modem cable for the tandy 100
TRS-80 portable. I guess they're called "pinouts". Thanks.

-Scott

[Charles Stephens]

sjk...@ritvax.isc.rit.edu (Scott J. Kleper) writes:

> I need a "map" of the pins for the modem cable for the tandy 100
> TRS-80 portable. I guess they're called "pinouts". Thanks.

Modem Port

1 TL Conventional Telephone Unit
2 GND Logic Ground
3 R x MD Direct Connection to Tel Line (RING)
4 R x MC Acoustic Coupler Connection (MIC)
5 T x MC Acoustic Coupler Connection (Speaker)
6 VDD RD for answering telephone
7 T x MD Direct Connection to Tel Line TIP
8 RP Ringing pulse
__ __
/8 |_| 7\
| 3 6 1 |
| 5 2 4 |
\_______/

Notes:

If you want to make your own modem cable that connects to a
RJ-11 modular jack, then connect the red and green wires (positions 3
and 4 on the jack) to pins 3 and 7. It doesn't matter how they are
connected because the M100/102/200 doesn't have ring detect. If you are
using an acoustic coupler, then a microphone should be connected to pins
4 and 6 and a speaker should be connected to pins 5 and 6. If you have
a ring detector that will output TTL signals, then hook that up to pin
8.

--
Charles Stephens,
Georgia Map coordinator,
SysOp of COW Pastures +1 404 421 0764
c...@cowpas.waffle.atl.ga.us

[Leonard Erickson]

sjk...@ritvax.isc.rit.edu (Scott J. Kleper) writes:

>I need a "map" of the pins for the modem cable for the tandy 100
>TRS-80 portable. I guess they're called "pinouts". Thanks.

I can't find the Model 100 manual (which has the pinouts) just
the service manual which is a bit cryptic.

pin tag use
1 TL tip side of phone line to attachd telephone
2 GND ground
3 RXMD ring side of phone line from wall (and passed to
attached telephone)
4 RXM ring side of acoustic coupler connection
5 TXM tip side of acoustic coupler connection
6 VDD +5 volts?
7 TXMD tip side of phone line from wall
8 RP ???

Note that pins 4 & 5 are only used when the switch is in the ACP position
pins 3 & 7 are only used when the switch is in the DIR position.

--
Leonard Erickson leo...@qiclab.scn.rain.com
CIS: [70465,203] 7046...@compuserve.com
FIDO: 1:105/51 Leonard....@f51.n105.z1.fidonet.org
(The CIS & Fido addresses are preferred)

[Joachim Astel]

c...@cowpas.waffle.atl.ga.us (Charles Stephens) writes:

Has anyone modified the Tandy 100 internal modem chip to support CCITT
instead of BELL with 300 bps? When I tried this I got only squeezing
noise... [my model is from 1983]

-Achim