PRO Null Modem Transfers›››                            1-17-90››                         Circular Logic›                          718-351-4304››It has recently come to our attention that many Pro SysOps are having›difficulty establishing a Null Modem transfer between their BBS and›a second computer, be it ST, IBM or XL.››It is quite easy and reliable as long as the correct cable is used.››The correct pinouts are as follows:››! Note: should you mess this up and blow up yourself or your neighborhood›we assume _no_ responsiblity! Get your pins right! They are labled on any›decent brand of connector.›Here are views looking at the 'business' ends of the connectors-›› Male DB9                        Female DB25›1 2 3 4 5          13 12 11 10 09 08 07 06 05 04 03 02 01› 6 7 8 9             25 24 23 22 21 20 19 18 17 16 15 14››       
›Atari 9 pin  to    Atari 9 Pin    or   IBM/ST 25 pin›____________       ___________          __________›1 DTR  *               1                   20 Data Terminal Ready *›2 CRX  *               2                    8 Data Carrier Detect *›3 XMT                  4                    3 Recieve Data›4 RCV                  3                    2 Transmitted Data›5 GND                  5                    7 Signal Ground›6 DSR                  6                    6 Not Cinnected›7 RTS                  7                    4 Request To Send›8 CTS                  8                    5 Clear To Send›9 NOT CONNECTED----------------------------------------------------››*** Note IMPORTANT inorder to work with Pro and or Express, Tie (short)›pins one and two (DTR/CRX) together on the XL end (and/or pins 8 & 20 on›the ST/IBM end) This insures a Carrier Detect for the BBS.››*Note: The only lines really needed are the lines on pins 1-5 on the›XL end (WITH the pin 1 & 2 mod as above). This swaps the Send/Recieve›lines and forces a carrier detect for the BBS and grounds both systems.››››After hooking up the cable and matching baud rates (BAUD.CMD by Circular›Logic serves nicely to temporarly step up your BBS baud rate for a ›null modem transfer) bang on the RETURN key on the remote system untill›the BBS 'sees' the keypress and starts the normal logon process.›Programs tested to work on the remote are: 850 Express, Express Cart,›Flash, DualTerm, Procomm Plus.››                  -Hope this helped!››                        -Tom & Bill›