Serial/Parallel Board (250-4034)       Settings       Faxback Doc. # 5486

There are hardware modifications for this board- 3000:017 and 4000:008

Standard board, comes with the Tandy 3000/3000HD/4000

This board comes standard with a DB-25 female parallel printer port and
a DB-9 male serial port

There are new ways of configuring LPT port addresses and assignments which
will affect the jumpering configurations of boards related to parallel
ports.

REFER TO TECHNICAL BULLETIN INFO:26 FOR FURTHER DETAILS ON CONFIGURING THIS
BOARD WITH THE 25-3049 MONOCHROME PARALLEL BOARD TOGETHER OR WITH THE NEWER
COMPUTERS (i.e., 4020/25/33LX series).

Serial/Parallel Board Revision "A" 25-4034:

E1-E3    Selects USA Standard baud-rate generator  (standard)
E1-E2 &  Selects International baud-rate
E3-E4    Selects International baud-rate

E6-E7    Selects parallel port 1 (LPT1) address 378-37F  (standard)
E5-E6    Selects parallel port 2 (LPT2) address 278-27F

E9-E10   Selects serial port 1 (COM1) address 3F8-3FF  (standard)
E8-E9    Selects serial port 2 (COM2) address 2F8-2FF

Serial/Parallel Board Revision "B" and "C" 25-4034:

E1-E3    Selects USA Standard baud-rate generator  (standard)
E1-E2 &  Selects International baud-rate
E3-E4    Selects International baud-rate

                             PORT SELECTION

________LPT1____________________        ________COM1_______________________
E6-E7    Selects address 378-37F        E9-E10   Selects address 3F8-3FF
E11-E12  Enables IRQ7                   E15-E16  Enables IRQ4

________LPT2____________________        ________COM2_______________________
E5-E6    Selects address 278-27F        E8-E9    Selects address 2F8-2FF
E13-E14  Enables IRQ5                   E17-E18  Enables IRQ3

Parallel Port (DB-25)
1   Strobe *            10  ACK *         (*) denotes active LOW signal
2   Data Bit 0          11  BUSY
3   Data Bit 1          12  PE
4   Data Bit 2          13  SLCT
5   Data Bit 3          14  AUTO FEED *
6   Data Bit 4          15  ERROR *
7   Data Bit 5          16  INIT *
8   Data Bit 6          17  SLCT IN *
9   Data Bit 7          18-25  GND

Serial Port (DB-9)
Adapter Cable 26-269 converts DB-9 to DB-25

DB-9 Connector (On 25-4034)     DB-25 Connector (26-269)
1  Carrier Detect-------------- 8
2  Receive Data---------------- 3
3  Transmit Data--------------- 2
4  Data Terminal Ready--------- 20
5  Signal Ground--------------- 7
6  Data Set Ready-------------- 6
7  Req. To Send---------------- 4
8  Clear To Send--------------- 5
9  Ring Indicate--------------- 22

1. Check the position of the Baud-Rate Generator jumper.  It is set at the
   factory to connect pins E1 and E3 for the USA Standard.  To set the
   Baud-Rate Generator to the International Standard connect pins E1 and E2
   with the jumper that connected E1 and E3.  Then connect pins E3 and E4
   with a second jumper.

2. If you are installing this board in the Tandy 3000, install a jumper on
   E5 and E6 to set the parallel port as Port 2 (LPT2).  Install a jumper
   on E8 and E9 to set the serial port as Port 2 (COM2).

3. If you are installing this board in the Tandy 1000 or Tandy 1200,
   install a jumper on E5 and E6 to set the parallel port as Port 2.  If a
   serial board is not already installed we suggest that you set the jumper
   on E9 and E10 to set the serial port as Port 1 (COM1).

NOTE: The parallel port can be set as Port 1 (LPT1) by moving the jumper to
connect pins E6 and E7.

NOTE: In order to resolve interrupt conflicts with other boards, disable the
corresponding interrupt on the Rev. B Serial/Parallel board by removing the
jumper from the corresponding interrupt staking pins as follows:

       INTERRUPT    STAKING PINS

          7         E11-E12
          5         E13-E14
          4         E15-E16
          3         E17-E18

Because of this, it is not recommended that 2 Rev. A Serial/Parallel Boards
be used in a computer.

(dkh/jej/jjs-08/26/96)