Serial Host Interface
Serial Host Interface Programming Model
MOTOROLA
DSP56367
9-7
The SHI interrupt vector table is shown in Table 9-1 and the exception priorities generated by
the SHI are shown in Table 9-2.
9.5.1
SHI INPUT/OUTPUT SHIFT REGISTER (IOSR)—HOST SIDE
The variable length Input/Output Shift Register (IOSR) can be viewed as a serial-to-parallel
and parallel-to-serial buffer in the SHI. The IOSR is involved with every data transfer in both
directions (read and write). In compliance with the I
2
C and SPI bus protocols, data is shifted
in and out MSB first. In 8-bit data transfer modes, the most significant byte of the IOSR is
used as the shift register. In 16-bit data transfer modes, the two most significant bytes become
the shift register. In 24-bit transfer modes, the shift register uses all three bytes of the IOSR
(see Figure 9-5).
Table 9-1 SHI Interrupt Vectors
Program Address
Interrupt Source
VBA:$0040
SHI Transmit Data
VBA:$0042
SHI Transmit Underrun Error
VBA:$0044
SHI Receive FIFO Not Empty
VBA:$0048
SHI Receive FIFO Full
VBA:$004A
SHI Receive Overrun Error
VBA:$004C
SHI Bus Error
Table 9-2 SHI Internal Interrupt Priorities
Priority
Interrupt
Highest
SHI Bus Error
SHI Receive Overrun Error
SHI Transmit Underrun Error
SHI Receive FIFO Full
SHI Transmit Data
Lowest
SHI Receive FIFO Not Empty
Summary of Contents for DSP56367
Page 16: ...xvi MOTOROLA CONTENTS Paragraph Number Title Page Number ...
Page 22: ...xxii MOTOROLA List of Figures Figure Number Title Page Number ...
Page 26: ...xxvi MOTOROLA List of Tables Table Number Title Page Number ...
Page 148: ...4 6 DSP56367 MOTOROLA Design Considerations PLL Performance Issues ...
Page 248: ...9 30 DSP56367 MOTOROLA Serial Host Interface SHI Programming Considerations ...
Page 306: ...10 58 DSP56367 MOTOROLA Enhanced Serial Audio Interface ESAI ESAI Initialization Examples ...
Page 389: ...Bootstrap ROM Contents MOTOROLA DSP56367 A 15 end ...
Page 390: ...A 16 DSP56367 MOTOROLA Bootstrap ROM Contents ...
Page 432: ...C 8 DSP56367 MOTOROLA JTAG BSDL ...
Page 484: ...D 52 DSP56367 MOTOROLA Programmer s Reference ...
Page 490: ...E 6 DSP56367 MOTOROLA Power Consumption Benchmark ...
Page 516: ...F 26 DSP56367 MOTOROLA IBIS Model ...
Page 522: ...Index 6 MOTOROLA Index ...
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