Freescale Semiconductor MPC5553 - Page 631

MPC5553/MPC5554 Microcontroller Reference Manual, Rev. 5
16-8 Freescale Semiconductor
16.3.2.2.5 Reset Configuration Halfword Read
The BAM program checks for a valid reset configuration halfword (RCHW, see Figure 16-4) at the first
location in external memory, i.e address 0x2000_0000.
If the BAM program fails to find a valid RCHW, it assumes the external memory does not contain a user
application and switches to serial boot mode.
If the BAM program does find a valid RCHW, it configures data pins and CS0 port size according to the
RCHW[PS0] bit and the e200z6 core watchdog according to the RCHW[WTE] bit. The watchdog timeout
Table 16-6. External Bus Interface Configuration
Pins
Reset
Serial Boot
Mode
1
or Internal Boot
Mode
1
This column is for serial boot mode only when entered directly using the BOOTCFG signals (See note 2).
External Boot with no
Arbitration
2
(Single Master Mode)
2
If serial boot is entered indirectly from either external boot mode because a valid RCHW was not found, the EBI
remains configured according to these columns.
External Boot with External
Arbitration
2
(Multi Master Mode)
Function Function Function PCR Function PCR
ADDR[8:31] GPIO GPIO ADDR[8:31] 0x0440 ADDR[8:31] 0X0440
DATA[16:31] GPIO GPIO GPIO
3
3
If the BAM reads a valid RCHW with the PS0 bit clear, data[16:31] are reconfigured from GPIO to data bus signals
by writing 0x0440 to the PCRs.
Default
3
GPIO
3
Default
3
DATA[0:15] GPIO GPIO DATA[0:15] 0X0440 DATA[0:15] 0X0440
BB
4
4
Signal enabled in the MPC5554.
GPIO GPIO GPIO Default BB 0X0443
BG
4
GPIO GPIO GPIO Default BG 0X0443
BR
4
GPIO GPIO GPIO Default BR 0X0443
TSIZ[0:1]
4
GPIO GPIO GPIO Default GPIO Default
TEA GPIO GPIO GPIO Default GPIO Default
CS0 GPIO GPIO CS0 0X0443 CS0 0X0443
WE0_BE0 GPIO GPIO WE0 0X0443 WE0_BE0 0X0443
OE GPIO GPIO OE 0X0443 OE 0X0443
TS GPIO GPIO TS 0X0443 TS 0X0443
TA GPIO GPIO GPIO Default GPIO Default
RD_WR GPIO GPIO GPIO Default GPIO Default
CS[1:3] GPIO GPIO GPIO Default GPIO Default
BDIP GPIO GPIO GPIO Default GPIO Default
WE[1:3]_
BE[1:3]
GPIO GPIO GPIO Default GPIO Default