Epson S1D13504 manual Bank Select Bits

Page 16	Epson Research and Development
	Vancouver Design Center

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 modes either bypass the LUT or have only Bank 0 starting at Index 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).

S1D13504	Programming Notes and Examples
X19A-G-002-07	Issue Date: 01/02/01