Hacking PC Pursuit (2600 Magazine, April, 1987)
By Cheshire Catalyst

PC Pursuit (PCP) is a service provided by Telenet (a division of U.S. Sprint) for $25 a month for use after business hours weekdays, and all day on weekends. You can use it during the business day for rates that will beat out long-distance voice, but not by much. Some interesting hacks have presented themselves in abusing, that is using, this service.

At the Telenet "@" prompt, a user types "CDIALXXX/12,USERNAME" where XXX is the area code of the modem near your destination, and 12 is the speed (1200 Bits Per Second (BPS)) you want to use at the destination modem. PCP provides you with a Username when you sign up for the service. We ll come back to the data rate later.

After you enter that command line, PCP then asks for a password. You are provided with a password by PCP, and cannot change it. You can have them change it, and send you the new password in the mail. After you type in your password, you are either connected to a "Hayes-compatible" modem in the distant city, or you are given the message "XXX BUSY," where XXX is once again the destination area code. As more people try to use the limited number of modems PCP has in what it thinks are major hotbeds of BBS action (Seattle?), more and more "busy signals" are encountered on the Net.

When placing your call to the remote modem, the number after the slash tells Telenet what speed to set up the connection at. Besides "12," "3" is also valid (for 300 BPS). However, "12" is valid even if you are calling into Telenet at 300 BPS, such as from a Tandy Model-100 (don't laugh; I'm preparing this article on a Model-100). Telenet is known as a "value added" network, and this is where it provides its "value added" services. The modem at the other end doesn't know if you are at 300, or 110, or even a synchronous mainframe with Ebenezer Scrooge for a system manager (watch for more "stingy manager" types to take advantage of these low rates).

It must be said, however, that if you download huge ASCII files via a 1200/300 connection, you may overload the network buffer with your transfer. If that happens, you will get an error message of "BUFFER OVERLOAD - SOME DATA HAS BEEN LOST." The thing to do is to send a Ctrl+S once in a while. The stuff will keep coming at you for a while, because of the speed differential, and when the network buffer finally empties, the transmission will stop. Naturally, a Ctrl+Q will start you up again, if your host hasn't logged you off for inactivity in the meantime. Protocol transfers only transfer 128 or so bytes at a time, and will be slow, but will not overflow buffers.

PCP says that the first thing you should do when you hit the modem is type "ATZ" to reset the modem. On the contrary. The first thing to do when Telenet reports "CONNECTED" is to type "A/," the Hayes command to repeat last command received. Most people will let their host hang up the connection, and then just hang up on PCP. In such a case, the last command given the modem was an "ATDT" command to place the call. The PCP modems are funny, though. If they have received an "ATZ," and therefore have no command in the command buffer, they will not echo a "/" character. This tells you to immediately go about your own business. When you've finished perusing the computer your PCP predecessor left in the modem, dial up your own machine.

When you re through with your computer, either it will hang up on you, or you must tell the modem to hang up on it. If you have to hang up, type "+++." You have just sent the "Hayes wake-up" command to two modems. Yours (assuming you have a Hayes compatible yourself), and the remote PCP modem in the distant city. Type "ATS2=65" followed by a return. You've just told your modem that it should only wake up when you type "AAA" (three capital A's) instead of "+++." Now type "ATO" to get back on line with PCP.

When we last left our remote modem, it was waiting for your command after receiving "+++" from you. Type "ATH" to hang it up. If you have other machines to dial in the remote city you've dialed, keep dialing (send the next "ATDT" command). If you ve called area code 212 and want to reach a Brooklyn BBS, type "ATDT17185393560," since the 718 area code is within the New York City LATA (Local Access and Transport Area). The same for calling Burbank (818) out of the LA area code, 213.

One friend of mine recently had the mistaken impression that PCP no longer went to the 415 area code. Sure, it's busy a lot, but that area's a busy hotbed of activity. To check out his claim, we got up on PCP and got busy message after busy message at 415/12. We decided to try 415/3 for a 300 BPS modem, and sure enough, we got one. It was slow as expletive, but we got there. Then our BBS in Berkeley was busy, and we were back to square one.

After you've had your fun, remember! Now is the time to hit "ATZ," before you hang up on the remote modem. When you're through with all the calls you want to make in the city you've reached, you should type the "ATZ" to your remote modem, and get back to Telenet to set you up with a call to a modem in another city. The best way is to type "@" followed by a carriage return. This will wake up Telenet, and give you an "@" prompt. Type "D" for Disconnect, and it will drop your connection to the modem in the city you had called. At the next "@" prompt, type "C DIALYYY/12,USERNAME" (YYY being the new area code), and begin the whole process again.

Are you in an area with multiple calling rates (such as New York City), with toll rates within the LATA? "Some people' are known to use PCP within their own area code (my modest nature and my constitutional rights preclude me saying any more). A caller in Manhattan can get his or her 25 bucks back quickly just by using PCP to call up BBS's on Long Island. Westchester also has some neat boards in 914 that are easy to hit this way.

So there you have it. Remember to "ATZ" the modem before you leave it. While the next caller can't find out what number is in the buffer, they can certainly get at least one call into whatever you've just hung up on. I ve even wound up on Teleconnect Magazine s BBS on an "A/," much to everyone's surprise.


Some of you may recall back in the early days, PC Pursuit had a rather unique system. You dialed a special number and entered all of your personal information ID code, password, and number you wanted to reach. PC Pursuit would then hang up and call you back at a predetermined number.

That system was limiting because you couldn t use it from more than one location. Some hackers claim to have gotten into their outgoing lines as they were dialing out and gained access in that way.

The way the system is set up now is almost acceptable. PC Pursuit must set up many more modems in many more cities before we sign up again.

It s also possible the way they have it working to tie up the entire system single-handedly. For example, from the Telenet number in New York, we could call the Telenet number in Seattle, enter our ID over there, call the Telenet number in Dallas, and set up a huge nationwide circle.

We saw this done once and the delay between the time a character was typed and the time it showed up on the screen was nearly 30 seconds! Needless to say, there were many busy signals that day.