Epson S1D13705 technical manual Screen-Register Relationship, Split Screen, LUT Address

Epson Research and Development	Page 65
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(REG[0Dh], REG[0Ch]) Words

Line 0 Last Pixel Address + REG[11h] Words

Line 0

Line 1

Image 1

		Line=(REG[13h], REG[12h])
	Image 2
		(REG[0Fh], REG[0Eh]) Words
		8(REG[04h]+1) Pixels
Where:		Virtual Image

(REG[0Dh], REG[0Ch]) is the Screen 1 Start Word Address BPP is Bits-per-Pixel as set by REG[02h] bits 7:6 REG[11h] is the Address Pitch Adjustment in Words (REG[0Fh], REG[0Eh]) is the Screen 2 Start Word Address (REG[13h], REG[12h]) is the Screen 1 Vertical Size (REG[06h], REG[05h]) is the Vertical Panel Size

Line 0 Last Pixel Address=((REG[0Dh], REG[0Ch]) +

(8(REG[04h]+1) ⋅ BPP/16))

Words

((REG[06h], REG[05])+1) Lines

REG[11h] Words

Figure 8-1: Screen-Register Relationship, Split Screen

Consider an example where REG[13h], REG[12] = 0CEh for a 320x240 display system. The upper 207 lines (CEh + 1) of the panel show an image from the Screen 1 Start Word Address. The remaining 33 lines show an image from the Screen 2 Start Word Address.

REG[15h] Look-Up Table Address Register
Address = 1FFF5h							Read/Write
LUT Address	LUT Address	LUT Address	LUT Address	LUT Address	LUT Address	LUT Address	LUT Address
Bit 7	Bit 6	Bit 5	Bit 4	Bit 3	Bit 2	Bit 1	Bit 0
bits 7-0	LUT Address Bits [7:0]
	These 8 bits control a pointer into the Look-Up Tables (LUT). The S1D13705 has three

256-position, 4-bit wide LUTs, one for each of red, green, and blue – refer to Section 11, “Look-Up Table Architecture” on page 71 for details.

This register selects which LUT entry is read/write accessible through the LUT Data Reg- ister (REG[17h]). Writing the LUT Address Register automatically sets the pointer to the Red LUT. Accesses to the LUT Data Register automatically increment the pointer.

For example, writing a value 03h into the LUT Address Register sets the pointer to R[3]. A subsequent access to the LUT Data Register accesses R[3] and moves the pointer onto G[3]. Subsequent accesses to the LUT Data Register move the pointer onto B[3], R[4], G[4], B[4], R[5], etc.

Note

The RGB data is inserted into the LUT after the Blue data is written, i.e. all three colors must be written before the LUT is updated.

Hardware Functional Specification	S1D13705
Issue Date: 02/02/01	X27A-A-001-10