Subject: Trident 8900 switch settings (someone archive this!)
From: j3gum@vax1.mankato.msus.edu
Organization: Mankato State University
Lines: 109

T8900DIP.TXT - Jeffrey E. Hundstad (j3gum@vax1.mankato.msus.edu)

                     Switch Settings on the Trident 8900C

----------------------------------\         /-----------------|
|                                  ---------                  |
|                                        9                ----|
| xx 8  8  8  8    -------                   -------      | 1
| xx               |  6  |                   |  10 |      |---|
|                  |     |  4                -------      | 2
| xx               ------ j1 j2                           |---|
| xx 8  8  8  8    -------       --------                 | 3
|                  |   5 |       |   5  |                 |---|
|--------------|   ------- |-|   --------    7   |-|          |
               |-----------| |-------------------| |-----------
                   VGA Graphics Adapter Layout #1 (8-DRAM)

----------------------------------\         /-----------------|
|                                  ---------      4 j3        |
|                  -------               9                ----|
| 11 8  8  8  8    |     |                  --------      | 1
|                  |  6  |                  |   10 |      |---|
|                  -------  4     -------   --------      | 2
|                          j2     |  5   |                |---|
| 11 8  8  8  8                   -------                 | 3
|                                 |  5   |           4 j1 |---|
|--------------|           |-|    --------   7   |-|          |
               |-----------| |-------------------| |-----------
                VGA Graphics Adapter Layout #2 (2/4/8 - DRAM)

----------------------------------\         /-----------------|
|                                  ---------        4 j3      |
|                  -------               9                ----|
| 11 8  8  8  8    |     |                  --------      | 1
|                  |  6  |         -------  |   10  |     |---|
|                  -------     4   |  5  |  --------      | 2
|                              j2  -------                |---|
| 11 8  8  8  8                    |  5  |                | 3
|                    4 j3          -------                |---|
|--------------|           |-|                   |-|   4 j1   |
               |-----------| |-------------------| |-----------
                VGA GRaphics Adapter Layout #3 (2/4/8 - DRAM)

1.  Dip Switches
2.  DB-15 connector: For analog monitors.
3.  DB-9 connector: for TTL monitors. (* NOTE #1)
4.  Jumers J1, J2, J3, J4 (J3 for layouts #2 and #3, J4 for layout #3)
5.  Video BIOS: Basic Input/Ouput System.
6.  TVGA 8900 Chip: VGA GRaphics chip.
7.  Edge connector: For IBM PC/XT, PC/AT and compatible systems.
8.  Video DRAM: up to 1MB
9.  Feature connector: For special applications.
10. Video DAC
11. Jumper Blocks JP1 and JP2 (2/4/8 board only)
* NOTE #1 - Hardware option.  Feature not present for all board versions.

Switch settings for the 6 switch dip box (#1 from figures).

Switch 3:  Scan Rate
  On  - Less than 48KHz (default)
  Off - 38-49Khz

Switch 5:  Fast and Slow Address Decode
  Off - Fast address decode (default)
  On  - Slow address decode

Switch 6:  8/16 bit Data Path
  Off - 16-bit data path (default)
  On  - 8-bit data path


Jumper settings

J1:  Settings for IRQ9
 1 2 3     1 2 3
   xxx     xxx
 Off (def)   On

J2:  Settings for Bus Size Detections
1           1 x
2 x         2 x
3 x         3
Autodetect  Standard Interface
(def)

J3:  Settings for DRAM Configuration
   1  2  3       1  2  3       1  2  3
   ----          |  |             ----
   ----          |  |             ----
   4  5  6       4  5  6       4  5  6

    Two DRAM      Four DRAM      Eight DRAM

J4:  DRAM Clock Select
 1 2 3     1 2 3
   xxx     xxx
 40 MHz    48 MHz
Two DRAM   4/8 DRAM


SW1 & SW2

Swich Setings       | SW1 | SW2
--------------------+-----+----
VGA mode (default)  | On  | On
EGA mode            | Off | On
CGA mode            | On  | Off
MDA/Hercules mode   | Off | Off

