Zyxel Modems And Apple Macintosh; Connector; Apple Macintosh Particularities - ZyXEL Communications 2864 Series User Manual

ZyXEL MODEMS AND APPLE
The external models of the 2864 series modems may be connected to an Apple
Macintosh computer. You may use the standard modem settings, with one excep-
tion: use AT&D0.

Connector

When you connect a ZyXEL modem to a Macintosh computer, make sure the cable
is a hardware handshaking cable. These cables are readily available. The models Li-
sa, Macintosh 128 and Macintosh 512 don't provide hardware handshaking. The
serial port on these (very outdated) models is provided as a 9-pin connector similar
to that of a PC. We will not discuss it here.
The serial port on all other Macintosh models is a Mini-8 connector.

Apple Macintosh Particularities

The Apple Macintosh serial port supports up to 57600 bps in interrupt mode start-
ing with the SE model. The modem port (A) also allows synchronous transfers. The
type of transfer is controlled through pin 7 of the serial port. This pin is connected
to the CD (Carrier Detect) line and the Receive/Send clock lines of the SCC circuit
(the serial port driver - comparable to, but more flexible than a PC UART). The
Chapter 23
MACINTOSH
8
7
5
4
2 1
Fig. 23.1: Serial port of an Apple Macintosh
6
3
23–1
1 DTR
2 CTS
3 TX -
4 GND
5 RX -
6 TD +
7 GPI
8 RX +