
MICROFIELD GRAPHICS, INC.

T8C

Category                 Video
Video Types Supported    CGA/EGA/VGA/XVGA
Video Processor          Trident
Highest Resolution       1280 x 1024
Supported
Data Bus Type            16-bit ISA
Memory Type              VRAM
Maximum Onboard Memory   2048KB

[Image]

                CONNECTIONS

          Purpose              Location

  15-pin analog video port        J1

                       EMULATION TYPE CONFIGURATION

           Type                 Address           JP1            JP1A

       VGA/EGA with High     3DDh - 3DEh      Pins 1 &2      Pins 1 & 2
           Resolution                           closed          closed

          CGA with High       3DDh - 3DEh      Pins 2 & 3     Pins 2 & 3
           Resolution                           closed          closed

        High resolution       3DDh - 3DEh      Pins 1 & 2     Pins 2 & 3
                                                closed          closed

        High resolution       30Dh - 30Eh      Pins 2 & 3     Pins 1 & 2
                                                closed          closed

            Note:Address setting 30Dh - 30Eh requires special device
            driver software for operation.

                        ALTERNATE I/O PORT ADDRESS

               Address                                 S6

                  3xx                         Pins 1 & 2 closed

                   1xx                         Pins 2 & 3 closed

             BIOS SIZE SELECT

        Size                 J10

        16KB          Pins 1 & 2 closed

        32KB          Pins 2 & 3 closed

                         VIDEO FREQUENCY SETTINGS

   Frequency           Mode              S1           S2           S7

  1280 x 1024     Non-interlaced     Pins 2 & 3   Pins 2 & 3      Open
                                       closed       closed

  1280 x 1024       Interlaced       Pins 2 & 3   Pins 1 & 2      Open
                                       closed       closed

  1280 x 1024     Non-interlaced     Pins 2 & 3   Pins 2 & 3     Closed
                                       closed       closed

  1024 x 768      Non-interlaced     Pins 1 & 2   Pins 1 & 2     Closed
                                       closed       closed

  Note: The last two settings require an optional dual crystal and 512KB
  microcode EPROM.

                            DMA CHANNEL SELECT

       DRQ              Dack                S5                 S8

          7              7             Pins 1 & 2      Pins 1 & 2 closed
                                          closed

           6              6             Pins 3 & 4      Pins 3 & 4 closed
                                          closed

           5              5             Pins 5 & 6      Pins 5 & 6 closed
                                          closed

                          VIDEO INTERRUPT SELECT

                  IRQ                                   S3

                   IRQ10                        Pins 3 & 4 closed

                    IRQ9                         Pins 1 & 2 closed

                    IRQ11                        Pins 5 & 6 closed

                    IRQ12                        Pins 7 & 8 closed

                  Disabled                      Pins 9 & 10 closed

                          MONITOR CONNECTOR SENSE

       Connector Sense                 J8                     J9

           Disabled           Pins 1 & 2 closed      Pins 1 & 2 closed

             Enabled           Pins 2 & 3 closed      Pins 2 & 3 closed

  Note: An optional microcode EPROM must be installed before Connector
  Sense can be enabled.

