
Static RAM (SRAM)
Freescale Semiconductor
6-5
move.l
#RAMVALID,D0
;load R valid bit into D0.
movec.l
D0, RAMBAR
;load RAMBAR and enable SRAM
The following loop initializes the entire SRAM to zero:
lea.l
RAMBASE,A0
;load pointer to SRAM
move.l
#8192,D0
;load loop counter into D0 (SRAM size/4)
SRAM_INIT_LOOP:
clr.l
(A0)+
;clear 4 bytes of SRAM
clr.l
(A0)+
;clear 4 bytes of SRAM
clr.l
(A0)+
;clear 4 bytes of SRAM
clr.l
(A0)+
;clear 4 bytes of SRAM
subq.l
#4,D0
;decrement loop counter
bne.b
SRAM_INIT_LOOP
;if done, then exit; else continue looping
6.3.2
Power Management
As noted previously, depending on the RAMBAR-defined configuration, instruction fetch and operand
read accesses may be sent to the SRAM and cache simultaneously. If the access maps to the SRAM
module, it sources the read data and the cache access is discarded. If the SRAM is used only for data
operands, setting the AS
n
bits associated with instruction fetches can decrease power dissipation.
Additionally, if the SRAM contains only instructions, masking operand accesses can reduce power
dissipation.
shows examples of typical RAMBAR settings.
Table 6-3. Typical RAMBAR Setting Examples
Data Contained in SRAM
RAMBAR[7:0]
Instruction Only
0x2B
Data Only
0x35
Instructions and Data
0x21
MCF5329 Reference Manual, Rev 3
Summary of Contents for MCF5329
Page 106: ...ColdFire Core 3 32 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 148: ...Cache 5 22 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 154: ...Static RAM SRAM 6 6 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 184: ...Power Management 8 18 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 204: ...Reset Controller Module 10 8 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 220: ...System Control Module SCM 11 16 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 228: ...Crossbar Switch XBS 12 8 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 268: ...General Purpose I O Module 13 40 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 392: ...SDRAM Controller SDRAMC 18 30 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 436: ...Fast Ethernet Controller FEC 19 44 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 594: ...FlexCAN 23 30 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 678: ...Pulse Width Modulation PWM Module 26 22 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 684: ...Watchdog Timer Module 27 6 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 704: ...DMA Timers DTIM0 DTIM3 29 12 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 754: ...UART Modules 31 34 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 770: ...I2 C Interface 32 16 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 866: ...Debug Module 36 50 Freescale Semiconductor MCF5329 Reference Manual Rev 3...