Bits 8–0

This register determines the starting address of Display Window 1 in the Display Page RAM. The

power-on default of 0x00 starts Window 1 at the beginning of the Page RAM (0x8000). This first

address location always contains the SL code for the first line of Display Window 1. This register is

new for the LM1236 and allows Window 1 to start anywhere in the Page RAM rather than just at

0x8000. Note that the address this points to in Page RAM must always contain the SL code for the

first line of the window.

Bits 15–9

These bits are reserved and should be set to zero.

Display Window 1 Column Width:

COLWIDTH1B3 (0x8417)

COLWIDTH1B2 (0x8416)

Window 1 Column Width - High Bytes

COL[31:16]

COLWIDTH1B1 (0x8415)

COLWIDTH1B0 (0x8414)

Window 1 Column Width - Low Bytes

COL[15:0]

Bits 31–0

These are the Display Window 1 Column Width 2x Enable Bits. These thirty-two bits correspond to

columns 31–0 of Display Window 1, respectively. A value of zero indicates the column will have

normal width (12 pixels). A “1” indicates the column will be twice as wide as normal (24 pixels). For

the double wide case, each Character Font pixel location will be displayed twice, in two

consecutive horizontal pixel locations. The user should note that if more than 32 display characters

are programmed to reside on a line, then all display characters after the first thirty-two will have

normal width (12 pixels).

Display Window 2 Horizontal Start Address:

HSTRT2 (0x8418)

Window 2 Horizontal Start Address

2H[7:0]

Bits 7–0

This register determines the horizontal start position of Window 2 in OSD pixels (not video signal pixels). The actual

position, to the right of the horizontal flyback pulse, is determined by multiplying this register value by 4 and adding

30. Due to pipeline delays, the first usable start location is approximately 42 OSD pixels following the horizontal

flyback time. For this reason, we recommend this register be programmed with a number larger than 2, otherwise

improper operation may result.

Display Window 2 Vertical Start Address:

VSTRT2 (0x8419)

Window 2 Vertical Start Address

2V[7:0]

Bits 7–0

This register determines the Vertical start position of Window 2 in constant-height character lines (not video scan

lines). The actual position is determined by multiplying this register value by 2. (Note: each character line is treated

as a single auto-height character pixel line, so multiple scan lines may actually be displayed in order to maintain

accurate position relative to the OSD character cell size. (See the Constant Character Height Mechanism section.)

This register should be set so the entire OSD window is within the active video.

Display Window 2 Start Address:

W2STRTADRH (0x841B)

W2STRTADRL (0x841A)

Reserved

Window 2 Start Address

XXXXXXX

2AD[8:0]

Bits 8–0

This register determines the starting address of Display Window 2 in the Display Page RAM. The power-on default

of 0x10 starts Window 2 at the midpoint of the Page RAM (0x8100). This location always contains the SL code for

the first line of Window 2.

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