User Manual

AT02876: Atmel REB212BSMA Hardware User Manual [APPLICATION NOTE]
Atmel-42097B-WIRELESS-AT02876-REB212BSMA-Hardware-User-Manual_ApplicationNote_062014
6
Pin# Function Pin# Function
31 PD7 (SLPTR) 32 PD6 (DIG2)
33 PD5 (TP2) 34 PD4 (open)
35 PD3 (TP3) 36 PD2 (IRQ)
37 PD1 (TP4) 38 PD0 (open)
39 GND 40 EE#WP (write protect EEPROM)
Note: 1. Possible by retrofitting a 0R assembly.
4.2 ID EEPROM
To identify the board type by software, an identification (ID) EEPROM (U5) is populated. Information about the
board, the node MAC address and production calibration values are stored here. A serial EEPROM AT25010B
[3] with 128 × 8-bit organization and SPI bus is used because of its small package and low-voltage and
low-power operation.
The SPI bus is shared between the EEPROM and the transceiver. The select signal for each SPI slave
(EEPROM, radio transceiver) is decoded with the reset line of the transceiver, RSTN. Therefore, the EEPROM is
addressed when the radio transceiver is held in reset (RSTN = 0; see Figure 4-2).
Figure 4-2. EEPROM Access Decoding Logic (Atmel ATmega1281 Configuration)
The EEPROM data is written during board production testing. A unique serial number, the MAC address, and
calibration values are stored. These can be used to optimize system performance. Table 4-3 shows a detailed
description of the EEPROM data structure.
Table 4-3. ID EEPROM Mapping
Address Name Type Description
0x00 MAC address uint64 MAC address for the 802.15.4 node, little endian byte order
0x08 Serial number uint64 Board serial number, little endian byte order
0x10 Board family uint8 Internal board family identifier
0x11 Revision uint8[3] Board revision number ##.##.##
>
1
>
1
PB
5
(
RSTN
)
SPI
PB
1
..
3
(
SPI
)
Transceiver
AT86RF212B
ID EEPROM
PB
0
(
SEL
)
RSTN
SELN
#CS