zic2410 California Eastern Laboratories, zic2410 Datasheet - Page 58

• Manufacturer Part Number: zic2410
• Description: Single-chip Solution, Compliant With Zigbee
• Manufacturer: California Eastern Laboratories

ZIC2410 Datasheet
1.8 MEDIUM ACCESS CONTROL LAYER (MAC)
The Medium Access Control (MAC) block processes a command received from the high layer
(MCU), transmits the data received from high layer to baseband modem, or encrypts it and then
transmits to baseband modem. In addition, it indicates the status of PHY and transmits the data
received from baseband modem to high layer, or transmits the decrypted data to high layer.
The function of the MAC block is to transfer the data from the higher layer to the PHY block, to
send the received data from the PHY to the higher layer with or without encryption or
decryption. Figure 29 shows the MAC block diagram.
Figure 29 – MAC block diagram
IEEE802.15.4 Frame Format
IEEE802.15.4 transmits the data in packets with each packet having a specified frame format.
Figure 30 shows a schematic view of the IEEE 802.15.4 frame format.
The PHY frame to be transmitted consists of preamble, start of frame delimiter (SOF), frame
length and PHY Service Data Unit (PSDU) fields. The Preamble is used to adjust the gain of
receiving signal and obtain synchronization at the received stage. The SOF is used to indicate
the starting position of the frame and obtain exact frame timing synchronization. Frame length
is 1 byte and is used to indicate the PSDU length which can vary up to a maximum of 127 bytes.
The PSDU contains the MPDU (MAC protocol data unit) as a payload.
The MPDU means the frame format generated in the MAC layer and it is consisted of frame
control field, data sequence number, address information, frame payload and Frame Check
Sequence (FCS) field.
The area, including a frame control field, a data sequence number field, and an address
information field, is defined as the MAC header. The FCS field is defined as the MAC footer.
The data which is transmitted from the higher layer is located in the MAC payload. For detailed
information on frame format, refer to the IEEE802.15.4 standard.
Rev A
Document No. 0005-05-07-00-000
Page 58 of 119