SPC8106 S-MOS Systems, SPC8106 Datasheet - Page 218

• Manufacturer Part Number: SPC8106
• Description: LCD/CRT VGA CONTROLLER
• Manufacturer: S-MOS Systems

Appendix D INITIALIZATION
D.1 (640x480 Single Color 8-Bit Display)
BIOS Functional Specification
SP2-48
1. Turn off the active video system.
2. Enable the SPC8106 Chip.
3. Default SPC8106 to 3DxH and 28 Mhz clock. This clock is guaranteed to be present.
4. Enable AUX registers.
5. Program AUX registers to required default values.
6. Set video memory to A000H to prevent conflicts with MDA/CGA cards by programming the graphic control-
7. We use Memory Data lines MD0-15 to set different chip states. These are usually set with DIP switches on
MOV
MOV
INT
3C3H = 1
3C2H = 67H
AUX[DEH] = 1AH
read AUX[DEH] data
AUX[0H] = 00000000b
AUX[1H] = 01000011b
AUX[2H] = 11000000b
AUX[3H] = 00000000b
AUX[4H] = 00000000b
AUX[5H] = 00000000b
AUX[6H] = 00000000b
AUX[7H] = 00000011b
AUX[9H] = 00000000b
AUX[0AH]= 00000000b
AUX[0BH]= 00000000b
AUX[0DH]= 00100000b
AUX[1AH]= 00000000b
AUX[1BH]= 00000000b
AUX[1CH]= 00000000b
AUX[1DH]= 00000000b
Graphics Controller [6H] = 04H; set A000H addressing
ler.
the board. Eight of these lines are readable in Auxiliary register 0CH (MD0-3 are bits 0-3, MD9-12 are bits 4-
7). They have no hardware effect so BIOS developers can redefine them freely. We use this information to
S-MOS Systems, Inc. • Tel: [phone] • Fax: [phone] • http://www.smos.com
AX,1201H
BL,32H
10H
; Setup function 12
; Video control
; Turn off active video system
; enable chip
; default to color addresses, 28 MHz clock
; write magic number to AUX[DEH]
; to complete enable cycle
; note: (DEH decodes to 0EH)
; IRQ disable, multifont disable,;
; B-Regs program disable, select LCD panel
; autocenter, slow cursor, NTSC, assume
; single panel
; CRT sprite, color panel, 8-bit data
; Full power
; Clear scratch register
; Disable second memory bank
; Disable page register at 3CD
; Stretch text and graphics
; No sprite memory mapping
; Clear scratch register
; LCD off, CRT off
; Set WF timing (may need modification)
; scratch pad
; scratch pad
; relative start address high
; relative start address high
X12-SP-002-03.1
411-1.0
SPC8106