SPC8106 S-MOS Systems, SPC8106 Datasheet - Page 219

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

SPC8106
8. Program the CRTC-B registers (CRTC-B[1H] and CRTC-B[12H]) to required frame rate and vertical panel
9. Wake up external RAMDAC. We assume the external RAMDAC is present. A more rigorous initialization
10. Turn on either display panel or CRT. In either case, we select external RAMDAC read. Enable panel display
11. Do standard VGA initialization.
12. Print signon message.
411-1.0
AUX[00H]b0 = 1
CRTC(3D4H) index 01H = 050H ; for 640 pixels wide panel
CRTC(3D4H) index 10H = 0
CRTC(3D4H) index 11H = 0
CRTC(3D4H) index 12H = 0F0H ; for a 480 single panel (8 MSB of 480)
CRTC(3D4H) index 15H = 0
AUX[00H]b0 = 0
AUX[0BH] = 00011110b
Initialize RAMDAC
AUX[0BH] = 00101010b
AUX[0BH] = 00100110b
set up interrupt vectors 42H, 10H, 6DH
do CGA/MDA detection
...
set mode 3 (or 7 if CGA present)
determine panel type (single or dual), DRAM refresh timing (32 or 4 ms) and power save mode 4/suspend
clock source select. If a hardware configuration is fixed these values could be hard coded in step 5 above.
The bits a developer will likely change are listed below.
sizes. This is done by enabling access to the B set registers, programming the values and then disabling ac-
cess to the B set.
code would do presence check here.
if no monitor is detected. We use AUX[08H] bits 0, 1, 2 (monitor ID bits) to detect the presence of a monitor.
If AUX[08H] & 07H = 07H, no monitor is present.
panel type
single/dual panel
refresh 32/4 ms
power down clock
WF timing
S-MOS Systems, Inc. • Tel: [phone] • Fax: [phone] • http://www.smos.com
If a monitor is detected enable the CRT.
AUX[0H] bits 5,6,7
AUX[1H] bit 0
AUX[2H] bit 0
AUX[2H] bits 2,3
AUX[0DH]
; enable B set read/write access
; TFT related
; TFT related
; 2 non-display lines
; disable B set r/w access
; enable writes to external DAC
; ctrl register
; enable LCD + External DAC read select
; disable writes to external DAC ctrl register
; enable anti-sparkle/power down RAMDAC
; (any time LCD is enabled with no CRT - power down
;
; enable CRT + External DAC read select
the RAMDAC)
X12-SP-002-03.1
BIOS Functional Specification
SP2-49