Functions
	spi_reset (void)
	reset/initialize the spi interface More...

	spi_begin (void)
	activate the spi interface

	spi_end (void)
	deactivate the spi interface

	spi_get_fifo_space (reg s)
	get status index of the least number of space in fifo More...

reg	spi_port (rint e)
	get a value from the SPI input port More...

	spi_send_loop_counter ()
	send the loop counter as a standard packet (packet size: 12 bytes)

	spi_aout (areg r)
	send an AREG plane as a standard packet (packet size: 65552 bytes) More...

	spi_aout64 (areg r)
	send a 64x64 subsample of an AREG plane as a standard packet (packet size: 4120 bytes) More...

	spi_dout (dreg r)
	send a DREG plane as a standard packet (packet size: 8208 bytes) More...

	spi_scan_events (dreg r, r_int16 n)
	scan and send the coordinates of `n` points in a DREG plane (packet size: 16 + 2*n bytes) More...

	spi_scan_target (dreg r)
	scan and send the coordinates of the bounding box of '1's in a DREG plane (packet size: 16 bytes) More...

	spi_send_header (r_int16 w)
	send a spi header, which containing the payload size. The size of the header itself is always 8 bytes. More...

	spi_send_byte (r_int v)
	send a value More...

	spi_set_transfer_size (r_int16 w)
	change the transfer size, which is the number of bytes in a single transfer burst More...

Detailed Description

Author: Jianing Chen

Function Documentation

spi_reset ( void )

reset/initialize the spi interface

This macro is usually used once before the beginning of the program.

Example Usage:

 ipu.reset_loop_counter
 
 // initialize spi interface
 spi_reset
 
 // main frame loop
 #start
     ipu.wait_frame_trigger
     rpix(B,C)
     
     ...
     
 _jump(#start)

spi_get_fifo_space ( reg s )

get status index of the least number of space in fifo

Parameters

[out] s the ipu register to store the index

This macro is mostly used to gurantee that the fifo has enough space to buffer the in-out speed mismatch in spi communication.

The absolute safe way to achieve this is the make sure the fifo space is bigger than the size of all packets used in a frame iteration.

reg spi_port ( rint e )

get a value from the SPI input port

Parameters

[in] e SPI input port option

Returns: the value presented in the port

The valid options for the input port is SPI_RX_0 to SPI_RX_7 .

See SPI Downwards Communication for some extra notes on receving data from host.

Example

The follow code use a value from SPI input port to threshold a image

 ...
 
 s0 = spi.port(SPI_RX_0)
 E = in(s0)
 D = sub(C,E)
 where(D)
 R5 = FLAG
 all
 spi.begin
 spi.dout(R5)
 spi.end
 ...

spi_aout ( areg r )

send an AREG plane as a standard packet (packet size: 65552 bytes)

Parameters

[in] r the AREG plane to be sent

spi_aout64 ( areg r )

send a 64x64 subsample of an AREG plane as a standard packet (packet size: 4120 bytes)

Parameters

[in] r the AREG plane to be sent

spi_dout ( dreg r )

send a DREG plane as a standard packet (packet size: 8208 bytes)

Parameters

[in] r the DREG plane to be sent

spi_scan_events	(	dreg	r,
		r_int16	n
	)

scan and send the coordinates of n points in a DREG plane (packet size: 16 + 2*n bytes)

Parameters

[in]	r	the DREG plane to be scanned
[in]	n	maximum number of points, can be a value between [0,65535]

spi_scan_target ( dreg r )

scan and send the coordinates of the bounding box of '1's in a DREG plane (packet size: 16 bytes)

Parameters

[in] r the DREG plane to be scanned

spi_send_header ( r_int16 w )

send a spi header, which containing the payload size. The size of the header itself is always 8 bytes.

Parameters

[in] w size of the payload

spi_send_byte ( r_int v )

send a value

Parameters

[in] v value to be sent

spi_set_transfer_size ( r_int16 w )

change the transfer size, which is the number of bytes in a single transfer burst

Parameters

[in] w number of bytes in a single transfer burst, between [16,4096]

This macro provide the optional setting of the transfer size, which may be used to optimize the spi communication for better bandwith or latency.

For more details about setting transfer size, see Optimizing Transfer Size.

Functions

Detailed Description

Function Documentation