A problem exists with Mac cables. Unless you're using the newer hispeed cable you can't connect to your ISP even tho it seems to test ok with a terminal program. I ran across this problem in trying to hook my Mac up. I fussed and fumed over it for about a month before stumbling across the solution. There is nothing to physically indicate any differences between the 2 cables. A little.Practical Peripherals file explains it as follows: The Macintosh has too few pins for a full RS-232 implementation. The RS-23 standard has 25 pins, however, most Mac ports have only 8 pins. The following pins are needed when talking to a high- speed modem: Input RX Output TX Clear to Send CTS Ready to Send RTS Data Terminal Ready DTR Carrier Detect DCD Ring Detect RI (can be done in software) Ground So if ring detect is covered in the software, you should only need 7 pins to handle communications. Unfortunately, the Mac ports double as RS-422 ports, and some of the pins are used to support this. Therefore the Mac only guarantees five or maybe six pins that can be used. While this wasn't a problem for 2400 bps modems, since they didn't require RTS/CTS, and even CD was rarely connected. You could just turn off your modem if it didn't hang up. This of course didn't work for BBS operators or ARA servers, so a cable was developed that used the RTS (usually called HSKo on the Mac) pin for DTR, and the CTS (usually called HSKi) pin for CD. As you can imagine, this cable configuration is a problem for high- speed modem users, since the RTS/CTS lines are used for CD and DTR. You couldn't take advantage of the full potential of your high- speed modem. That is why a new "standard" hardware handshake cable layout was developed. Here's the pin outs for that cable: Function (Mac) Function (RS-232) Pin (Mac) Pin (RS-232) Receive data Receive data 5 3 Send data Send data 3 2 Ground Ground 4 & 8 7 HSKi CTS 2 5 HSKo RTS & DTR 1 4 & 20 GPi CD 7 8 Unfortunately, not all Macs support Pin 7 (GPi) thus leaving us with keeping CD on at all times. Also, since DTR is tied to RTS a high- speed modem must be set to ignore any change in DTR. Otherwise an RTS flow control change would cause the modem to hang up the telephone line. If both your Macintosh and your hardware handshake cable support Pin 7, then you could properly track changes in DCD, but setting the modem to track DTR will still cause the modem to hang up when RTS is toggled. END Perhaps this is the problem Marion is wrestling with. ciao larry Reply to: lgwalker(a)look.ca

The whole port thing on the Mac is a real can of worms. On reading your post I went scurrying to my puter specs and tips directory and computer books and my head is still spinning. Aside from the variance of connectors; the m.128-512 with DB(DE?)9, the Mac+ - Mac ll(?) with 8pin mini-DINs and the later models with 9pin mini-DINs not to mention the ethernet AUUI 15 or the abortive HDI-45 monitor port and the cabling problem, you have to contend with Apples nominclature. I have various Macs including a 512,+, SE, IIci,and LCIII, as well as various Apple printers. Labeling the cables would seem to be my best solution. The 9pin miniDIN adds a +5 v source on pin9 but the sockets are backward compatible. The hi-speed cable I use is an 8pin miniDIN. My PowerMac gives these specs: Pin Name Function --- ---- -------- 1 SCLK(out) Reset pod or get pod attention 2 Sync(in)/SCLK(in) Serial clock from pod 3 TxD- Transmit - 4 Gnd/shield Ground 5 RxD- Receive - 6 TxD+ Transmit + 7 Wakeup/TxHS Wake up CPU or do DMA handshake 8 RxD+ Receive + 9 +5 V Power to pod (350 mA maximum) So it uses the previously not-used pin 7 with no reference to Carrier Detect, unless that's what they mean with "wake up CPU". And (of course !) Apple uses new names for it's ports since HSK didn't catch on. I guess a "pod" is a serial device not something that grows on vines or a space capsule. :^) I've got about a dozen or so Mac books except the reputedly "best" Larry Pina one, and none of them mention this problem. I've also got a NEXT which IIRC uses RS423 prot. but has a similiar miniDIN. These guys really keep the cable manufacturers busy. Again the specs are hard to find. Is there such a thing as a repositry of cable connection specs ? ciao larry Reply to: lgwalker(a)look.ca

Anybody using one of those little (size of a RS232 gender bender) boxes with leds for all the status pins? What about a RS232 breakout thingie?

ROTFL. I'll have to keep this beside my bench to inject a bit of humor and perspective the next time I'm ready to do serious damage to either the equipment or myself. These were right from the Apple PPC manual specs for the serial modem port. "Keep 'em confused and they'll keep coming back". ciao larry Reply to: lgwalker(a)look.ca

Sorry to do this but I haven't seen any of my posts yet.

On 05-Oct-2000 Mike Ford wrote: *snip* I'm looking for the reverse of this. I have a Worldport with a mini-din plug that I want to connect to a friend's wintel portable. I managed to get a 3 wire protocol (RX, TX, GND) going, so I can "AT" the modem and get "OK" back. But if I dial an ISP, I'll get "CONNECT 12345" (don't recall the speed) and then nothing. I suspect it's waiting for some handshaking I don't have (and haven't found) proper documenation for the modem. Maybe there exists an ATSx=y code or extended command would deactivate the handshaking while connected. Anyone have a clue? -Philip