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P5040/P5020 Reference Design Board User Guide, Rev. 0
24
Freescale Semiconductor
Architecture
This table lists RCW sources.
5.1.14
I
2
C
The reference design board uses three of the four I
2
C buses on the P5040/P5020.
•
I
2
C1 is electrically isolated before P5040/P5020 power-up to allow external or FPGA I
2
C masters
to program Zilker power devices.
•
I
2
C2 and I
2
C4 can function independently, or together with I
2
C2 as the controller.
This table summarizes I
2
C bus device addresses while
shows overall I
2
C scheme connections.
Table 13. Reset Configuration Word Source
Value (Binary)
Reset Configuration Signal Name
Description
0_0000
CFG_RCW_SRC[4...0]
I
2
C1 normal addressing supports ROMs up to 256 bytes.
0_0001
I
2
C1 extended addressing
0_0010
Reserved
0_0011
Reserved
0_0100
SPI 16-bit addressing
0_0101
SPI 24-bit addressing
0_0110
eSDHC
0_0111
Reserved
0_1000
eLBC FCM (NAND FLASH, 8-bit small page)
0_1001
eLBC FCM (NAND FLASH, 8-bit large page)
0_1010
Reserved
0_1011
Reserved
0_1100
eLBC GPCM (NOR FLASH, 8-bit)
0_1101
eLBC GPCM (NOR FLASH, 16-bit)
0_1110
Reserved
0_1111
Reserved
1_0000 -1_1011
Hard-coded RCW options
1_1100-1_1111
Reserved
Table 14. I
2
C Bus Device Map
1
I
2
C Bus
I
2
C Address
Device
Notes
1
0x22
LTC3889: VCORE PM Bus (TBD)
Controls rail VDD_CORE.
1
0x24
LTC3876 regulator: DDR PM Bus (TBD)
Controls rail VDD_GVDD.