AN2621 Freescale Semiconductor / Motorola, AN2621 Datasheet - Page 14

• Manufacturer Part Number: AN2621
• Description: MPC8220i PF300 Image Coprocessor Operation
• Manufacturer: Freescale Semiconductor / Motorola

Appendix D
Screening Unit C Code
Data types:
PF300 initial condition register definitions:
Temporary registers:
Screening loops:
14
Uint32
Sint32
Uint8
Uint1
Adding a "*" to any of the data types indicates it is the address of
a value of the specified type.
Adding a "*" to a reference to a data type means use the value
pointed to by the variable for the operation.
Uint8 *tilep;
Uint32 tileo;
Uint32 tx;
Uint32 ty;
Uint32 txo;
Uint32 tyo;
Uint32 dx;
Uint32 dy;
Uint1 *dest;
Uint32 txc;
Uint32 tyc;
Uint8 *tp;
Uint8 pixel;
Uint32 x;
Uint32 y;
// Initialize the current vertical location in the tile
tyc = tyo;
// Loop over the number of lines in the destination
for (y = 0; y <= dy; y++)
{
// Reset the current horizontal location in the tile to inital pos.
txc = txo;
// Calculate the address of the initial position in tile.
// tileo is incremented/wrapped at the bottom of the vertical loop.
tp = tilep + tileo + txo;
// Loop over the number of pixels in a line of the destination
for (x = 0; x <= dx; x++)
// unsigned 32-bit integer.
// signed 32-bit integer.
// unsigned 8-bit integer.
// Single bit value
// Current horizontal position in tile
// Current vertical position in tile
// Pointer to current value in tile
// Value of the current input pixel
// Current horizontal position in destination
// Current vertical position in destination
// Pointer to top left pixel of tile
// Offset in bytes to left most pixel on initial line
// Number of pixels in horizontal dimension of tile
// Number of pixels in vertical dimension of tile
// Initial horizontal position within tile (phase)
// Initial horizontal position within tile (phase)
// Number of pixels to step horizontally in destination
// Number of pixels to step vertically in destination
// Address to store result
MPC8220i PF300 Image Coprocessor Operation
Freescale Semiconductor, Inc.
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