BeagleBone BBONEBLK_SRM, Справочное руководство

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REF: BBONEBLK_SRM
BeagleBone Black System
Reference Manual
Rev A5.2
Page 87 of 108
8.2.4 EEPROM Data Format
Table 14 shows the format of the contents of the expansion board EEPROM. Data is
stored in Big Endian with the least significant value on the right. All addresses read as a
single byte data from the EEPROM, but two byte addressing is used. ASCII values are
intended to be easily read by the user when the EEPROM contents are dumped.
Table 14. Expansion Board EEPROM
Name
Offset Size
(bytes)
Contents
Header 0 4 0xAA, 0x55, 0x33, 0xEE
EEPROM Revision 4 2 Revision number of the overall format of this EEPROM in ASCII =A1
Board Name 6 32 Name of board in ASCII so user can read it when the EEPROM is dumped. Up to
developer of the board as to what they call the board..
Version 38 4 Hardware version code for board in ASCII. Version format is up to the developer.
i.e. 02.1… 00A1....10A0
Manufacturer 42 16 ASCII name of the manufacturer . Company or individual’s name.
Part Number 58 16 ASCII Characters for the part number. Up to maker of the board.
Number of Pins 74 2 Number of pins used by the daughter board including the power pins used.
Decimal value of total pins 92 max, stored in HEX.
Serial Number 76 12
Serial number of the board. This is a 12 character string which is:
WWYY&&&&nnnn
where: WW = 2 digit week of the year of production
YY = 2 digit year of production
&&&&=Assembly code to let the manufacturer document the assembly number
or product. A way to quickly tell from reading the serial number what the board
is. Up to the developer to determine.
nnnn = incrementing board number for that week of production
Pin Usage 88 148
Two bytes
for each configurable pins of the 74 pins on the expansion
connectors MSB LSB
Bit order: 15 14 ……………1..0
Bit 15…………..Pin is used or not…… .. … ...0=Unused by cape 1=Used by cape
Bit 14- 13………Pin Direction………… . ..….1 0=Output 01=Input 11=BDIR
Bits 12- 7………Reserved……………………should be all zeros
Bit 6……….… . .Slew Rate …………………..0=Fast 1=Slow
Bit 5…….…… . .Rx Enable…………………..0=D isabled 1=Enabled
Bit 4……….… . .Pull Up/Dn Select…………..0=Pulldown 1=PullUp
Bit 3…………. . .Pull Up/DN enabled………..0=Enabled 1=Disabled
Bits 2- 0 ……… . Mux Mode Selection………..Mode 0 -7
VDD_3V3B Current 236 2 Maximum current in milliamps. This is HEX value of the current in decimal
1500mA=0x05 0xDC 325mA=0x01 0x45
VDD_5V Current 238 2 Maximum current in milliamps. This is HEX value of the current in decimal
1500mA=0x05 0xDC 325mA=0x01 0x45
SYS_5V Current 240 2 Maximum current in milliamps. This is HEX value of the current in decimal
1500mA=0x05 0xDC 325mA=0x01 0x45
DC Supplied 242 2
Indicates whether or not the board is supplying voltage on the VDD_5V rail and
the current rating 000=No 1-0xFFFF is the current supplied storing the decimal
equivalent in HEX format
Available 244 32543 Available space for other non-volatile codes/data to be used as needed by
the manufacturer or SW driver. Could also store presets for use by SW.