mrf24j40 Microchip Technology Inc., mrf24j40 Datasheet - Page 16

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

4.2
4.2.1
The short address space is accessed by sending a ‘0’
as the first bit of the SPI transfer. The following 6 bits
are the address of the target register. The final bit of the
first byte 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 4-3:
EXAMPLE 4-1:
DS39776A-page 14
MRF24J40
SDO
SCK
SDI
CS
BYTE GetShortRAMAddress(BYTE address)
{
}
Short Address Register Interface
0
READING SHORT ADDRESS
REGISTERS
A5
BYTE toReturn;
CSn = 0;
SPIPut((address<<1)&0b01111110);
toReturn = SPIGet();
CSn = 1;
return toReturn;
A4
SHORT ADDRESS READ
SHORT ADDRESS READ EXAMPLE
A3
A2
A1
Advance Information
A0
0
D7
D6
D5
D4
X
D3
© 2006 Microchip Technology Inc.
D2
D1
D0