Chip Configuration Module (CCM)
MCF52277 Reference Manual, Rev. 1
9-4
Freescale Semiconductor
9.3.2
Reset Configuration Register (RCON)
At reset, the RCON register determines the default operation of certain chip functions. All default
functions defined by the RCON values can be overridden only during reset configuration (see
Section 9.4.1, “Reset Configuration
”) if the external BOOTMOD[1:0] pins are driven to 10 or 11. RCON
is a read-only register and contains the same fields as the CCR register, except for DRAMSEL.
Table 9-4. CCR Field Descriptions
Field
Description
15–9
Reserved, must be cleared.
8
DRAMSEL
FlexBus/SDRAM data pin configuration. Reflects the chosen data bus configuration as determined by
BOOTMOD[1:0], FB_A21, or SBF_RCON29 as shown below:
Note:
If DRAMSEL is cleared, only 8-bit and 16-bit port sizes are allowed.
0 D[31:16] = SDRAM DDR data[31:16]
D[15:0] = FlexBus data[31:16]
1 D[31:0] = SDRAM SDR data[31:0] or FlexBus data[31:0]
7–6
CSC
Chip select configuration. Reflects the chosen chip select configuration.
00 FB_A[23:22] = FB_A[23:22]
01 FB_A[23:22] = FB_CS5, A22
10 FB_A[23:22] = FB_CS[5:4]
11 Reserved
5
LIMP
Limp mode bit.
0 Normal operation; PLL drives internal clocks.
1 Limp mode; low-power clock divider drives internal clocks.
4
LOAD
Pad driver load bit. Reflects the chosen pad driver strength for those pins with drive strength control and the
chosen pad slew rate for those pins with slew rate control.
0 Low drive strength, low slew rate
1 High drive strength, high slew rate
3–2
BOOTPS
Boot port size field. Indicates the selection for the boot port size.
00 32 bits
01 8 bits
10 16 bits
11 16 bits
Note:
32-bit port size cannot be selected when the DRAMSEL is 0.
1
OSCMODE
Oscillator clock mode bit.
0 Crystal oscillator mode
1 Oscillator bypass mode
0
Reserved, must be set.
BOOTMOD[1:0]
DRAMSEL
00
1
Unified SDR bus/FlexBus
01
0
Split DDR bus/FlexBus
10
FB_A21
Override defaults via data bus (FB_A[21:16]).
11
SBF_RCON29
Override defaults via serial boot.
Содержание MCF52277
Страница 1: ...MCF52277 Reference Manual Devices Supported MCF52274 MCF52277 Document Number MCF52277RM Rev 1 04 2008...
Страница 22: ...MCF52277 Reference Manual Rev 1 Freescale Semiconductor xxii...
Страница 32: ...MCF52277 Reference Manual Rev 0 xxxii Freescale Semiconductor...
Страница 60: ...Signal Descriptions MCF52277 Reference Manual Rev 1 2 16 Freescale Semiconductor...
Страница 112: ...Enhanced Multiply Accumulate Unit EMAC MCF52277 Reference Manual Rev 1 4 20 Freescale Semiconductor...
Страница 128: ...Static RAM SRAM MCF52277 Reference Manual Rev 1 6 6 Freescale Semiconductor...
Страница 140: ...Clock Module MCF52277 Reference Manual Rev 1 7 12 Freescale Semiconductor...
Страница 172: ...Chip Configuration Module CCM MCF52277 Reference Manual Rev 1 9 16 Freescale Semiconductor...
Страница 180: ...Serial Boot Facility SBF MCF52277 Reference Manual Rev 1 10 8 Freescale Semiconductor...
Страница 188: ...Reset Controller Module MCF52277 Reference Manual Rev 1 11 8 Freescale Semiconductor...
Страница 210: ...Crossbar Switch XBS MCF52277 Reference Manual Rev 1 13 8 Freescale Semiconductor...
Страница 480: ...Liquid Crystal Display Controller LCDC MCF52277 Reference Manual Rev 1 21 44 Freescale Semiconductor...
Страница 510: ...Touchscreen Controller Analog to Digital Converter MCF52277 Reference Manual Rev 1 22 30 Freescale Semiconductor...
Страница 542: ...FlexCAN MCF52277 Reference Manual Rev 1 23 32 Freescale Semiconductor...
Страница 568: ...Pulse Width Modulation PWM Module MCF52277 Reference Manual Rev 1 24 26 Freescale Semiconductor...
Страница 640: ...Programmable Interrupt Timers PIT0 PIT1 MCF52277 Reference Manual Rev 1 27 8 Freescale Semiconductor...
Страница 690: ...DMA Serial Peripheral Interface DSPI MCF52277 Reference Manual Rev 1 29 40 Freescale Semiconductor...
Страница 724: ...UART Modules MCF52277 Reference Manual Rev 1 30 34 Freescale Semiconductor...
Страница 740: ...I2 C Interface MCF52277 Reference Manual Rev 1 31 16 Freescale Semiconductor...
Страница 790: ...Debug Module MCF52277 Reference Manual Rev 1 32 50 Freescale Semiconductor...