
Random Number Generator (RNG)
34-4
Freescale Semiconductor
34.2.3
RNG Entropy Register (RNGER)
The RNGER is a write-only register which allows the user to insert entropy into the RNG. This register
allows an external user to continually seed the RNG with externally generated random data. Although use
of this register is recommended, it is optional. The RNGER can be written at any time during operation.
Each time the RNGER is written, the value updates the internal state of the RNG. The update is performed
in such a way that the entropy in the RNG’s internal state is preserved. Use of the RNGER can increase
the entropy but never decrease it.
34.2.4
RNG Output FIFO (RNGOUT)
The RNGOUT provides temporary storage for random data generated by the RNG. As long as the FIFO
is not empty, a read of this address returns 32 bits of random data. If the FIFO is read when it is empty,
RNGSR[EI, FUF, LRS] are set. If the interrupt is enabled in RNGCR, an interrupt is triggered to the
interrupt controller. The RNGSR[OFL], described in
Section 34.2.2, “RNG Status Register (RNGSR)
,”
can be polled to monitor how many 32-bit words are currently resident in the FIFO. A new random word
pushes into the FIFO every 256 clock cycles (as long as the FIFO is not full). It is very important to poll
RNGSR[OFL] to make sure random values are present before reading from RNGOUT.
1
LRS
Last read status. Reflects status of most recent read of the FIFO.
0 During last read, FIFO was not empty.
1 During last read, FIFO was empty (underflow condition).
0
SV
Security violation. When enabled by RNGCR[HA], signals that a FIFO underflow has occurred. Bit is sticky and is
only cleared by hardware reset.
0 No violation occurred or RNGCR[HA] is cleared.
1 Security violation (FIFO underflow) has occurred.
Address: 0xEC08_8008 (RNGER)
Access: User write-only
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10
9
8
7
6
5
4
3
2
1
0
R
W
ENT
Reset 0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Figure 34-3. RNG Entropy Register (RNGER)
Address: 0xEC08_800C (RNGOUT)
Access: User read-only
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10
9
8
7
6
5
4
3
2
1
0
R
Random Output
W
Reset 0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Figure 34-4. RNGOUT
Table 34-3. RNGSR Field Descriptions (continued)
Field
Description
MCF5329 Reference Manual, Rev 3
Содержание MCF5329
Страница 106: ...ColdFire Core 3 32 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 126: ...Enhanced Multiply Accumulate Unit EMAC 4 20 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 148: ...Cache 5 22 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 154: ...Static RAM SRAM 6 6 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 184: ...Power Management 8 18 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 204: ...Reset Controller Module 10 8 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 220: ...System Control Module SCM 11 16 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 228: ...Crossbar Switch XBS 12 8 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 268: ...General Purpose I O Module 13 40 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 392: ...SDRAM Controller SDRAMC 18 30 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 436: ...Fast Ethernet Controller FEC 19 44 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 564: ...Liquid Crystal Display Controller LCDC 22 44 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 594: ...FlexCAN 23 30 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 678: ...Pulse Width Modulation PWM Module 26 22 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 684: ...Watchdog Timer Module 27 6 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 692: ...Programmable Interrupt Timers PIT0 PIT3 28 8 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 704: ...DMA Timers DTIM0 DTIM3 29 12 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 720: ...Queued Serial Peripheral Interface QSPI 30 16 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 754: ...UART Modules 31 34 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 770: ...I2 C Interface 32 16 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 790: ...Message Digest Hardware Accelerator MDHA 33 20 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 866: ...Debug Module 36 50 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 902: ...Register Memory Map Quick Reference A 26 Freescale Semiconductor MCF5329 Reference Manual Rev 3...