TWO-COLOR ATTRIBUTE RAM

This address range (0x8440–0x8497) contains the attribute lookup tables used for displaying two-color characters. There are 16

groups of 4 bytes each according to the format shown in Table 13. The attributes are stored starting with Color 0 (background)

and each color is stored red first, green second and then blue. They may be written or read using the following address format:

where: N = Attribute number (0x0

≤ N ≤ 0xF)

B = Attribute byte number (0x0

≤ B ≤ 0x3)

When reading, it is OK to read only one, two, or all three bytes. When writing more than one 2-color attribute using the auto

increment feature, all four bytes must be written. When writing, bytes 0 through 2 must be written in order. Bytes 0 through 2 will

take effect after byte 2 is written. Since byte 3 contains all reserved bits, this byte may be written, but will have no effect. Any bits

marked as “X” are reserved and should be written to with zeros and should be ignored when the register is read.

TABLE 13. LM1236 Two-Color Attribute Registers

Register

Address

D7

D6

D5

D4

D3

D2

D1

D0

ATT2C0n

0x8440 + 4n

C0B[1:0]

C0G[2:0]

C0R[2:0]

ATT2C1n

+1

C1B[0]

C1G[2:0]

C1R[2:0]

C0B[2]

ATT2C2n

+2

X

X

EF[3:0]

C1B[2:1]

ATT2C3n

+3

XXXXXXXX

FOUR-COLOR ATTRIBUTE RAM

This address range (0x8500–0x857F), contains the attribute lookup tables used for displaying four-color characters. There are 16

groups of 8 bytes each according to the format shown in Table 14. The attributes are stored starting with Color 0 (background)

and each color is stored red first, green second and then blue. They may be written or read using the following address format:

where: N = Attribute number (0x0

≤ N ≤ 0xF)

B = Attribute byte number (0x0

≤ B ≤ 0x7)

When writing, bytes 0 through 2 must be written in order and bytes 4 through 6 must be written in order. Bytes 0 through 2 will

take effect after byte 2 is written. Bytes 4 through 6 will take effect after byte 6 is written. Since bytes 5 and 7 contain all reserved

bits, these bytes may be written, but no effect will result. When reading, it is OK to read only one, two, or all three bytes. If writing

more than one 4-color attributes using the auto increment feature, all eight bytes must be written. Any bits marked as “X” are

reserved and should be written to with zeros and should be ignored when the register is read.

TABLE 14. LM1236 Four-Color Attribute Registers

Register

Address

D7

D6

D5

D4

D3

D2

D1

D0

ATT4C0n

8500 + (n*8)

C0B[1:0]

C0G[2:0]

C0R[2:0]

ATT4C1n

+1

C1B[0]

C1G[2:0]

C1R[2:0]

C0B[2]

ATT4C2n

+2

X

X

EF[3:0]

C1B[2:1]

ATT4C3n

+3

XXXXXXXX

ATT4C4n

+4

C2B[1:0]

C2G[2:0]

C2R[2:0]

ATT4C5n

+5

C3B[0]

C3G[2:0]

C3R[2:0]

C2B[2]

ATT4C6n

+6

XXXXXX

C3B[2:1]

ATT4C7n

+7

XXXXXXXX

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