Sensoray 614 Caption Overlay - Manual (Page 12)

BbCh[5:0] is for choosing which bitmap-block or character font stored in the bitmap-block RAM: i.e.
BbCh[5:0] = 0: choose Bitmap-block or Char #0, stored/started at 400 h
BbCh[5:0] = 1: choose Bitmap-block or Char #1, stored/started at 408 h
: :
BbCh[5:0] = 62: choose Bitmap-block or Char #62, stored/started at 5f0 h
BbCh[5:0] = 63: choose Bitmap-block or Char #63, stored/started at 5f8 h
For Window-5 and Window-6:
Each Bitmap-Block is composed of 16-bit/word x 8 words, which holds 8 pixels x 16 lines of one bitmap-block data
or one character font (8 pixels x 16 lines, if in text mode).
RAM Bitmap-Block #0~7, Data: 800 h – 83f h
RAM Bitmap-Block #8~15, Data: 840 h – 87f h
RAM Bitmap-Block #16~23, Data: 880 h – 8bf h
RAM Bitmap-Block #24~31, Data: 8c0 h – 8ff h
RAM Bitmap-Block #32~39, Data: 900 h – 93f h
RAM Bitmap-Block #40~47, Data: 940 h – 97f h
RAM Bitmap-Block #48~55, Data: 980 h – 9bf h
RAM Bitmap-Block #56~63, Data: 9c0 h – 9ff h
Then, two windows of caption/overlay attributes will be followed, to determine which bitmap block(s) or character font(s),
with what color and transparent attribute, will be chosen to fill the caption/overlay windows/fields.
RAM Window-#1, Attributes: a00 h – a3f h
RAM Window-#2, Attributes: a40 h – a7f h
Attribute Formation:
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
R/W Transp Y2 Y1 Y0 U2 U1 U0 V2 V1 V0 BbCh5 BbCh4 BbCh3 BbCh2 BbCh1 BbCh0
DEFAULT 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0