Chameleon-PIC Nurve Networks, Chameleon-PIC Datasheet - Page 191

• 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

Example(s):
data = GFX_Read_Mem_Port8() ;
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Function Prototype:
Description:
Example(s):
GFX_Write_Mem_Port8( 0xFF ) ;
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Function Prototype:
Description:
Example(s):
int GFX_Write_Mem_Port8(unsigned int data);
unsigned int GFX_Read_Mem_Port16(void);
Read the byte of memory currently pointed to by the source memory pointer.
Write $FF to the byte of memory currently pointed to by the source memory pointer.
Read the 16-bit WORD of memory currently pointed to by the source memory pointer.
Thus, the variable tile_mem_autoinc_parm is used as the memory increment stride each read/write
operation. This comes in handy and reduces address updates when you access continuous memory.
There is of course a function to change tile_mem_autoinc_parm.
GFX_Write_Mem_Port8() writes an 8-bit value to prop_memory[ source_ptr ] = data, 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.
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
Thus, the variable tile_mem_autoinc_parm is used as the memory increment stride each read/write
operation. This comes in handy and reduces address updates when you access continuous memory.
There is of course a function to change tile_mem_autoinc_parm.
Finally, the function always returns 1.
GFX_Read_Mem_Port16() reads a 16-bit value from prop_memory[ source_ptr ] , note source pointer
is always used for memory port operations. 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 16-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
Thus, the variable tile_mem_autoinc_parm is used as the memory increment stride each read/write
operation. This comes in handy and reduces address updates when you access continuous memory.
There is of course a function to change tile_mem_autoinc_parm.
' update src pointer based on auto increment value
' update src pointer based on auto increment value
© 2009 NURVE NETWORKS LLC “Exploring the Chameleon PIC 16-Bit”
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