Matrix Orbital GLK24064-25 Legacy - Manual (Page 22)

4.2.10 Direct screen write bitmap (254 100 [x1][y1][x2][y2][data]{[data]})
This command is used to draw a bitmap to the screen directly without first storing it in the file space.
This is a far quicker method of drawing a bitmap to the screen than using individual pixels. There are some
irregularities and limitations to this command.
Unlike the format of bitmap download, this command expects data to be sent horizontally instead of
vertically. The first byte of data is located in the top left of the area defined by (x1,y1) and the MSB of that
byte is the left-most pixel. The second byte is the next 8 pixels to the right of the first byte. While each
individual byte is oriented as one would expect, with LSB toward the right and the bytes moving from left to
right across the screen, it’s not a ’bit-stream’ as might be expected. After the first pixel row of data is sent,
data continues on the next pixel row.
The definitions of [x1] and [x2] must lie on ’byte boundaries’. That is, [x1] and [x2] must be defined as
0x00, 0x08, 0x10, etc. It is not possible to write a 10x10 bitmap to the screen at pixel location (13,13). It is
however, possible to write a 16x10 bitmap to the screen at pixel location (24,13).
Use flow control during direct screen bitmap writes to avoid possible buffer overflow.
4.2.11 Initialize strip chart (254 106 [ref][x1][y1][x2][y2])
A ’strip chart’ is an area of the screen reserved for horizontal scrolling. This is normally used as follows;
1. Initialize the strip chart. This reserves the appropriate area of the screen.
2. Draw a line segment at the right or left side of the strip chart.
3. Shift the strip chart to the right or left.
4. Draw the next line segment.
Used this way, the strip chart can produce a graph which scrolls smoothly horizontally in either direction.
With text the strip chart can produce a ’marquis’ effect.
NOTE If the strip chart is used with text we recommend the use of a 6 or 7 pixel wide
fixed width character set, with each character placed 8 pixels from the start of the previous
one.
Up to 7 strip charts ([ref] = 0 - 6) may be defined. To initialize a strip chart the user must define an area on
the display in which to place the strip chart. (x1,y1) is the top left corner of the area to be used, where [x1] is
the placement of the column where the strip chart is to begin and [y1] is the row. The user must then define
[x2] as the bottom right column of the area to be utilized and [y2] as the bottom right row.
The definition of x must lie on ’byte boundaries’. That is, x must be defined as 0x00, 0x08, 0x10, etc.
This restriction does not apply to y values.
4.2.12 Shift strip chart (254 107 [ref])
This command shifts the strip chart left or right. [ref] determines both which strip chart is used and
which direction it will shift. The direction is selected by the most significant bit (MSB);
MSB = 0 shifts left
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