User`s manual
Rastergraf  
3-12 Programming On-board Devices 
Display Memory Size 
The pixel size is programmable to 8, 15, 16, or 32 bpp. The SGRAM on 
the Borealis is either 16 MB or 32 MB, where a MB = 1024 * 1024 bytes. 
Calculate the possible display formats based on these values. 
Note that you can render into SGRAM that is not being used in the active 
display, and by changing the starting address register in the Borealis pan 
to it so it is visible or BitBLT the Pixmap data to a static display window. 
3.5 Eclipse3 Optional Features Register 
Although most functions on the Eclipse3 are self-contained, it is necessary 
to maintain a few extra control bits for supplementary features. Using the 
Micrel MIC74 I
2
C 8-bit I/O register, the graphics board supports an 
auxiliary register. 
All bits come up tristate and have pullups except I2CMUX which has a 
pull down. 
Table 3-2 Eclipse3 ACR Register Bit Assignments 
Bit  Mnemonic  Value  Function  Description 
0 REDLED  0 
1 
on 
off 
Red LED 
1 AMBLED  0 
1 
on 
off 
Amber LED 
2 GRNLED  0 
1 
on 
off 
Green LED 
3 I2CMUX  1 
0 
local 
monitor 
Switches the Borealis DDC2B/I2C 
control lines between local devices 
(THC63DV164, Serial EEPROM, and 
LM75) and the display monitor. 
5, 4  --  -    not used  -- 
6 PBSEL  0 
1 
high bank
low bank 
Selects between the high and low 64 
KB of Flash PROM when JP101 is not 
installed. 
JP101( installed) overrides this bit 
(forces low). 
7 --  -    not used 










