Freescale Semiconductor DSP56374 User Manual page 58

Operating Modes
Mode MODD MODC
0 0 0
1 0 0
2 0 0
3 0 0
4 0 1
5 0 1
6 0 1
7 0 1
8 1 0
9 1 0
A 1 0
B 1 0
C 1 1
D 1 1
E 1 1
F 1 1
Mode 0 Reserved
Mode 1 Reserved
Mode 2 The DSP starts fetching instructions from the starting address of the on-chip Program ROM. SHI operates in
SPI slave mode.
Mode 3 Reserved
Mode 4 Reserved
Mode 5 In this mode, the internal PRAM is loaded from the Serial Host Interface (SHI). The SHI operates in the SPI
slave mode, with 24-bit word width.The bootstrap code expects to read a 24-bit word specifying the number
of program words, a 24-bit word specifying the address to start loading the program words and then a 24-bit
word for each program word to be loaded. The program words will be stored in contiguous PRAM memory
locations starting at the specified starting address. After reading the program words, program execution starts
from the same address where loading started.
Mode 6 Same as Mode 5 except SHI interface operates in the I
filter enabled.
Mode 7 Same as Mode 5 except SHI interface operates in the I
Mode 8 Reserved
4-2
Table 4-2. DSP56374 Operating Modes
Reset
MODB MODA
Vector
0 0 $000000 Reserved
0 1 $FF0000 Reserved
1 0 $FF0000 Jump to PROM starting address (slave SPI mode)
1 1 $FF0000 Reserved
0 0 $FF0000 Reserved
0 1 $FF0000 Bootstrap from SHI (slave SPI mode)
1 0 $FF0000 Bootstrap from SHI (slave I
1 1 $FF0000 Bootstrap from SHI (slave I
0 0 $004000 Reserved
0 1 $FF0000 Bootstrap from SHI (Serial I
1 0 $FF0000 Reserved
1 1 $FF0000 Bootstrap from SHI (Serial SPI EEPROM mode)
0 0 $FF0000 Bootstrap from GPIO (Serial SPI EEPROM mode)
0 1 $FF0000 Jump to PROM at default HLX (slave SPI)
1 0 $FF0000 Jump to PROM starting address (slave I
1 1 $FF0000 Jump to PROM starting address (slave I
Table 4-3. DSP56374 Mode Descriptions
DSP56374 Users Guide, Rev. 1.2
Description
2
C mode)
(HCKFR=1, 100ns filter enabled)
2
C mode)
(HCKFR=0)
2
C EEPROM mode)
(HCKFR=1, 100ns filter enabled)
(HCKFR=0)
(HCKFR=1, 100ns filter enabled)
2
C slave mode with HCKFR set to 1 and the 100ns
2
C slave mode with HCKFR set to 0.
2
C)
2
C)
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