mrf24j40 Microchip Technology Inc., mrf24j40 Datasheet - Page 18

• Manufacturer Part Number: mrf24j40
• Description: Ieee 802.15.4? 2.4 Ghz Rf Transceiver
• Manufacturer: Microchip Technology Inc.

4.3
4.3.1
The long address space is accessed by sending a ‘1’
as the first bit of the SPI transfer. The following 10 bits
are the address of the target register. The final bit is a
‘0‘ to indicate that the command is a read. On the next
clock edge of SCK, the Most Significant bit of the
register will shift out, followed by the rest of the bits.
FIGURE 4-5:
EXAMPLE 4-3:
DS39776A-page 16
MRF24J40
SDO
SCK
SDI
CS
BYTE GetLongRAMAddress(WORD address)
{
}
Long Address Register Interface
READING LONG ADDRESS
REGISTERS
1
BYTE toReturn;
CSn = 0;
SPIPut(((address>>3)&0b01111111)|0x80);
SPIPut(((address<<5)&0b11100000));
toReturn = SPIGet();
CSn = 1;
return toReturn;
A9
A8
LONG ADDRESS READ
LONG ADDRESS READ EXAMPLE
A7
A6
A5
A4
A3
Advance Information
A2
A1
A0
0
X
D7
D6
D5
© 2006 Microchip Technology Inc.
X
D4
D3
D2
D1
D0