Page 16 Epson Research and Development
Vancouver Design Center
S1D13504 Programming Notes and Examples
X19A-G-002-07 Issue Date: 01/02/01
Bank Select Bits
LUT banks are provided to give the application developer a choice of colors/gray shades. While the
chosen color depth (bpp) may limit the simultaneous colors available, the panel is capable of storing
different combinations of colors in banks. This is useful when an application developer chooses to
set Bank 0 to low intensity colors and set Bank 1 to high intensity. The application can easily switch
between low intensity output and high intensity output by using one register write.
Only two display modes support these bits: 2 bpp and 8 bpp. All other mo des either bypass the LUT
or have only Bank 0 starting at Inde x 00h.
In 2 bpp mode, the 16 entry LUTs are logically split into 4 groups of 4 entries for each of R, G, B.
Bank 0 = Indexes 00-03h
Bank 1 = Indexes 04-07h
Bank 2 = Indexes 08-0Bh
Bank 3 = Indexes 0C-0Fh
In 8 bpp mode, the 16 entry LUTs are logically split into 2 groups of 8 entries for both Red and Green
as follows:
Bank 0 = Indexes 00-07h
Bank 1 = Indexes 08-0Fh
For Blue the 16 entry LUT is logically split into 4 groups of 4 entries as follows:
Bank 0 = Indexes 00-03h
Bank 1 = Indexes 04-07h
Bank 2 = Indexes 08-0Bh
Bank 3 = Indexes 0C-0Fh
The bank select bits only affect data output. CPU access to the LUT indexes are done directly as in
the example below:
To program index 3 of the current LUT, with Green bank select bits set to 11b and 2 bpp gray shade
mode selected, you would program LUT address to [[3(bank select value)*4(entries in
LUT]+3(index to modify)-1(to zero-base the value)]=14(0Eh).