mc56f8335 Freescale Semiconductor, Inc, mc56f8335 Datasheet - Page 105

• Manufacturer Part Number: mc56f8335
• Description: 16-bit Digital Signal Controller
• Manufacturer: Freescale Semiconductor, Inc

will clear it. Basically, when the EXTR bit is 1, the previous system reset was caused by the external
RESET pin being asserted low.
6.5.2.5
When 1, the POR bit indicates a Power-On Reset occurred some time in the past. This bit can be cleared
only by software or by another type of reset. Writing a 0 to this bit will set the bit, while writing a 1 to the
bit position will clear the bit. In summary, if the bit is 1, the previous system reset was due to a Power-On
Reset.
6.5.2.6
This bit field is reserved or not implemented. It is read as 0 and cannot be modified by writing.
6.5.3
Only SIM_SCR0 is shown in this section. SIM_SCR1, SIM_SCR2, and SIM_SCR3 are identical in
functionality.
6.5.3.1
This register is reset only by the Power-On Reset (POR). It has no part-specific functionality and is
intended for use by a software developer to contain data that will be unaffected by the other reset sources
(RESET pin, software reset, and COP reset).
6.5.4
This read-only register displays the most significant half of the JTAG ID for the chip. This register reads
$01F4.
6.5.5
This read-only register displays the least significant half of the JTAG ID for the chip. This register reads
$401D.
Freescale Semiconductor
Preliminary
Base + $2
Base + $6
RESET
Read
Write
Read
Write
POR
SIM Software Control Registers (SIM_SCR0, SIM_SCR1, SIM_SCR2,
and SIM_SCR3)
Most Significant Half of JTAG ID (SIM_MSH_ID)
Least Significant Half of JTAG ID (SIM_LSH_ID)
Power-On Reset (POR)—Bit 2
Reserved—Bits 1–0
Software Control Data 1 (FIELD)—Bits 15–0
15
15
Figure 6-6 Most Significant Half of JTAG ID (SIM_MSH_ID)
0
0
0
Figure 6-5 SIM Software Control Register 0 (SIM_SCR0)
14
14
0
0
0
13
13
0
0
0
12
12
0
0
0
56F8335 Technical Data, Rev. 5
11
11
0
0
0
10
10
0
0
0
9
0
9
0
0
FIELD
8
8
0
1
1
7
7
0
1
1
6
6
0
1
1
5
0
5
1
1
4
0
4
1
1
3
3
0
0
0
2
0
2
1
1
Register Descriptions
1
0
1
0
0
0
0
0
0
0
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