Re: ][c null modem problems...

[Chris Morse <chris@cosmicwolf.com>]

On Wed, 30 Jul 2003 16:11:40 -0700, "Paul Grammens" <grammens@svn.net>
wrote:

>
>"Chris Morse" <chris@cosmicwolf.com> wrote
>> SNIP >>
>> I got a mini DIN-8 to DB25 "high speed" modem cable from Intrec along
>> with a copy of ProTERM.
>> SNIP >>
>> // CHRIS
>>
>
>The IIc+ serial port is not exactly the same as a IIgs or Mac serial port,
>even though it uses the same connector.
>
>Here is a pinout I used to make a cable which worked:
>
>IIc+                      DB-25
>2                            20
>5                             2
>4                              7
>3                              3
>1                        (show no connection, but maybe pin 6)
>
>-Paul

Hiya Paul,

I was reading on their site about doing file transfers -- I think
maybe the quick solution to my problem is getting a copy of an Apple
IIGS To Printer serial cable, which is supposed to pass off as a null
modem cable.

Anyhow, here's what I came up with.  This is using the "MultiSpeed
Modem Cable" from Intrec.com which I got at the same time I purchased
a copy of ProTERM A2 v3.1.

I used a digital ohm-meter to test all the pin connections.  This is
how the "Multi-Speed Modem cable" is wired, along with the //c+ serial
port pin info taken directly from my copy of the Apple IIc Technical
Reference Manual, 2nd Edition:

Guess I'll make a trip up to CompUSA and try to get that printer
cable.  Would be nice if I didn't have to frankenstein a cable
together.

Cheers!
// CHRIS



[View with fixed-pitch font to preserve ASCII Art diagrams]



*
* Apple IIc Plus Serial Port Modem Connector
*


Apple IIc Plus Serial Port Connectors

       ____     
    .-'    `-.  
   /   8 7 6  \ 
  (   5 4   3  )
   \   2  1   /
    `-.____.-' 

	Pin  Signal  Description
	---  ------  -----------------------
	 1   DTR1B   Data Terminal Ready output
	     DTR2B
	     
	 2   DSR1B   Data Set Ready input
	     DSR2B
	     
	 3   TD1B    Transmit Data output
	     TD2B
	 
	 4   GND     Power And Signal Common
	     
	 5   RD1B    Read Data input
	     RD2B
	
	 6   GND     Power And Signal Common
	
	 7   (Not Specified In IIc Tech Ref Manual 2nd Edition)
	
	 8   (Not Specified In IIc Tech Ref Manual 2nd Edition)
	

	A2Central describes the pinouts the same, but with 
	pins 4, 6 and 8 as GND (Ground) and pin 7 not connected.


*
* Intrec "MultiSpeed Modem Cable"  Mini DIN8 To DB25
*

	DIN8  DB25 [EIA RS-232-C Standard Connection Name]
	----  ----
	  1     5  [CTS = Clear To Send]
	  2     4 *and* 20  [RTS = Request To Send *and* DTR = Data
Terminal Ready]
	  3	3  [RD = Receive Data]
	  4	7  [SG = Signal Ground]
	  5	2  [TD = Transmit Data]
	  6	7  [SG = Signal Ground]
	  7	8  [CD = Carrier Detect]
	  8	(No Connection)

(END)