jdevoto@Apple.COM (Jeanne A. E. DeVoto) (12/30/90)
In article <dpaight.662534816@weber.ucsd.edu> dpaight@weber.ucsd.edu (Daniel Paight) writes: >Sorry if this is the 4.23e06 time this question has been raised >here, but I need someone to tell me how to null modem. My >father-in-law has bought a Mac and needs to move his data files from >a CP/M Kaypro to the Mac. I thought null modeming sounded like a >promising way to go, but I'm ignorant about electronics and such and >am afraid I might blow up his new Mac! :) > >I understand only this much: that I need a special cable to connect >the Mac modem port directly to the Kaypro's RS232. I have found a >source for the cable, but I'd like to find out what I'm getting into >before pursuing this any further. Please help! A serial port has separate lines for transmit and receive. A "null modem" simply reverses these lines, so that the transmit pin on one end is connected to the receive pin on the other end. (The lines used for handshaking will be flipped also, if they're connected.) This means that what you send from one computer gets sent to the "receive" pin on the other computer. All it is is a special kind of cable. No possibility of blowing anything up. -- ========= jeanne a. e. devoto ======================================== jdevoto@apple.com | You may not distribute this article under a jdevoto@well.sf.ca.us | compilation copyright without my permission. ______________________________________________________________________ Apple Computer and I are not authorized | CI$: 72411,165 to speak for each other. |
Daniel.Paight@f20.n226.z1.FIDONET.ORG (Daniel Paight) (12/30/90)
Reply-To: dpaight@weber.ucsd.edu
Sorry if this is the 4.23e06 time this question has been raised
here, but I need someone to tell me how to null modem. My
father-in-law has bought a Mac and needs to move his data files from
a CP/M Kaypro to the Mac. I thought null modeming sounded like a
promising way to go, but I'm ignorant about electronics and such and
am afraid I might blow up his new Mac! :)
I understand only this much: that I need a special cable to connect
the Mac modem port directly to the Kaypro's RS232. I have found a
source for the cable, but I'd like to find out what I'm getting into
before pursuing this any further. Please help!
Dan Paight
--
Daniel Paight - via FidoNet node 1:105/14
UUCP: ...!{uunet!glacier, ..reed.bitnet}!busker!226!20!Daniel.Paight
INTERNET: Daniel.Paight@f20.n226.z1.FIDONET.ORGJeanne.A..E..DeVoto@f20.n226.z1.FIDONET.ORG (Jeanne A. E. DeVoto) (12/30/90)
Reply-To: jdevoto@Apple.COM In article <dpaight.662534816@weber.ucsd.edu> dpaight@weber.ucsd.edu (Daniel Paight) writes: >Sorry if this is the 4.23e06 time this question has been raised >here, but I need someone to tell me how to null modem. My >father-in-law has bought a Mac and needs to move his data files from >a CP/M Kaypro to the Mac. I thought null modeming sounded like a >promising way to go, but I'm ignorant about electronics and such and >am afraid I might blow up his new Mac! :) > >I understand only this much: that I need a special cable to connect >the Mac modem port directly to the Kaypro's RS232. I have found a >source for the cable, but I'd like to find out what I'm getting into >before pursuing this any further. Please help! A serial port has separate lines for transmit and receive. A "null modem" simply reverses these lines, so that the transmit pin on one end is connected to the receive pin on the other end. (The lines used for handshaking will be flipped also, if they're connected.) This means that what you send from one computer gets sent to the "receive" pin on the other computer. All it is is a special kind of cable. No possibility of blowing anything up. -- ========= jeanne a. e. devoto ======================================== jdevoto@apple.com I You may not distribute this article under a jdevoto@well.sf.ca.us I compilation copyright without my permission. ______________________________________________________________________ Apple Computer and I are not authorized I CI$: 72411,165 to speak for each other. I + Organization: Apple Computer Inc., Cupertino, CA -- Jeanne A. E. DeVoto - via FidoNet node 1:105/14 UUCP: ...!{uunet!glacier, ..reed.bitnet}!busker!226!20!Jeanne.A..E..DeVoto INTERNET: Jeanne.A..E..DeVoto@f20.n226.z1.FIDONET.ORG
aem@mthvax.cs.miami.edu (a.e.mossberg) (12/31/90)
>In article <dpaight.662534816@weber.ucsd.edu> dpaight@weber.ucsd.edu >(Daniel Paight) writes: >>Sorry if this is the 4.23e06 time this question has been raised >>here, but I need someone to tell me how to null modem. My >>father-in-law has bought a Mac and needs to move his data files from >>a CP/M Kaypro to the Mac. I thought null modeming sounded like a >>promising way to go, but I'm ignorant about electronics and such and >>am afraid I might blow up his new Mac! :) In <47632@apple.Apple.COM> jdevoto@Apple.COM (Jeanne A. E. DeVoto) writes: >[...] >All it is is a special kind of cable. No possibility of blowing anything >up. UNLESS YOU HAVE ONE OF THE LIMITED EDITION MACS THAT HAD A 4KV LINE COMING OUT THE SERIAL PORT! sorry aem -- aem@mthvax.cs.miami.edu ....................................................... Buchwald's Law: As the economy gets better, everything else gets worse.
derosa@motcid.UUCP (John DeRosa) (01/03/91)
jdevoto@Apple.COM (Jeanne A. E. DeVoto) writes: >>I understand only this much: that I need a special cable to connect >>the Mac modem port directly to the Kaypro's RS232. I have found a >>source for the cable, but I'd like to find out what I'm getting into I have found that a Imagewriter I (not II or LQ) cable works great. It is null modem from 8 pin to 25 pin "D". Of course an IBM P.C. uses a 9 bin "D" for its serial ports (and a 25 pin "D" for the parallel ports {which caused me some sleepless nights}), so you will need a 9 to 25 pin adapter. -- = John DeRosa, Motorola, Inc, Cellular Infrastructure Group = = e-mail: ...uunet!motcid!derosaj, motcid!derosaj@uunet.uu.net = = Applelink: N1111 = =I do not hold by employer responsible for any information in this message =