Arrow DECA User Manual page 98

Figure 7-5 shows the system block diagram of this reference design. The main program is NIOS
Program running at on-chip memory located in FPGA. The I2C Opencore IP controller is used by
NIOS to communicate with the Si1143 chip. There is a relevant C-code library in NIOS program to
communicate with "I2C Opencore" controller. When we using I2C Opencore API, we need to make
sure to shift one bit left from the original 7-bit I2C Slave to become 8-bit address value (ex:
0x01->0x02). JTAG UART module is used to let user dump information. Si1143 will send out
interrupt signal in specific situation, so a PIO is needed to receive the interrupt signal from Si1143.
Our demo shows 2 types of operations by press KEY[0] on DECA board to switch operation type.
 Operation in type 1
Our default demo is Type1, running NIOS will execute PS_FORCE command to renew the data in
Proximity Sensing (PS) Register of irLED. Then NIOS will read PS Register and display on NIOS
Terminal, the output data indicate the strength of Proximity Sensing of irLED as shown in
7-6.
DECA User Manual
Figure 7-5 Block Diagram of the Si1143 Demonstration
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Figure
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May 22, 2015