Chameleon-PIC Nurve Networks, Chameleon-PIC Datasheet - Page 190

• Manufacturer Part Number: Chameleon-PIC
• Description: MCU, MPU & DSP Development Tools PIC24 & PROPELLER DEV SYSTEM (SBC)
• Manufacturer: Nurve Networks

Specifications of Chameleon-PIC

• Processor To Be Evaluated: PIC24
• Data Bus Width: 16 bit
• Interface Type: USB, VGA, PS/2, I2C, ISP, SPI
• Operating Supply Voltage: 3.3 V, 5 V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

GFX_Write_Bitmap_Ptr( GFX_Read_Bitmap_Ptr() + 256 );
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Function Prototype:
Description:
Example(s):
int fine_scroll ;
fine_scroll = GFX_Get_Vscroll() ;
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Function Prototype:
Description:
Example(s):
for (int scroll = 0; scroll < 8; scroll++)
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Function Prototype:
Description:
{
GFX_Set_VScroll( scroll );
_delay_ms(100);
} // end for scroll
int GFX_Get_VScroll(void);
int GFX_Set_VScroll(int vscroll);
unsigned int GFX_Read_Mem_Port8(void);
Read the vertical scroll register.
Fine scroll 8 times in about a second from 0..7, a tile height.
GFX_Get_VScroll() returns the current fine vertical scroll value from 0..7. The tile engine supports
smooth vertical scrolling via the vertical fine scroll register. This function reads that register.
GFX_Set_VScroll(…) sets the vertical fine scroll register with the sent value vscroll (0..7). Use this
function and register to control smooth scrolling. Each tile is 8 pixels high, thus you can scroll the tilemap
up and down a single pixel at a time with this register/call. To perform continuous smooth scrolling, first
fine scroll 0..7 then reset to 0, and course scroll a single row. Returns 1.
GFX_Read_Mem_Port8() reads a 8-bit value from prop_memory[ source_ptr ] , note source pointer is
always used for memory port operations (read or write). In the Propeller driver source_ptr is the variable
tile_src_addr_parm and is set using GFX_Set_Src_Ptr(unsigned int src_ptr) defined below. The idea
of this function is that it provides a simple mechanism to access the Propeller’s RAM. Returns the 8-bit
value read directly from the Propeller’s 32K RAM. This function also updates the source pointer
automatically anticipating another read or write. The actual code looks like:
tile_src_addr_parm += tile_mem_autoinc_parm
' update src pointer based on auto increment value
© 2009 NURVE NETWORKS LLC “Exploring the Chameleon PIC 16-Bit”
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