SDI Technologies SDIO Card - Manual (Page 23)

©Copyright 2002-2006 SD Card Association
SDIO Card Bluetooth Type-A Simplified Specification Version 1.00
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Basis transfer mode. When the Type-A Transport in the Host receives an interrupt from the Packet Read
Ready signal, it starts to read the Type-A Transport packet from the Card. This interrupt signal shall be
issued for receipt of Type-A Transport packets instead of receipt of SDIO data packets. The Type-A
Transport header is read first, and it is used to determine the length of the Type-A Transport packet. The
Type-A Transport in the Host then reads the entire Type-A Transport packet as SDIO data packets are
concatenated in Byte Basis transfer mode until the total length of received SDIO data reaches the Type-
A Transport packet length. It then sets the PCRRT to "0" to indicate the success of packet read
operation to the Type-A Transport in the Card. Finally it removes the Type-A Transport packet header
and informs the Type-A Host Control Interface of the arrival of a new data packet.
When a CRC error occurs in SDIO transmission, the Type-A Transport in the Host recognizes it through
the transmission result. It aborts multi block transfer and sets the PCRRT field to "1" in order to prepare
for a re-read, and the Type-A Transport in the Card issues an interrupt to the Host. When the interrupt is
cleared, it shall try to re-read the Type-A Transport data packet, until the erroneous packet is received
successfully or a number of retries designated by the Host are reached. If the packet is not received
successfully, the Type-A Transport sends a fatal error to the Host application. The Host application
should reset the Type-A Transport to resume Bluetooth communication.
Figure 11 – Type-A Transport Packet Read Operation from the Card to the Host in Block
Basis Transfer Mode
Length (3 Bytes) Service ID (1 Byte) Interface data (L-4 Bytes)
Data (4 Bytes) Data ((L – 4) mod B)
SDIO
Protocol
Multiplexing
Adaptation
Type-A Transport
SDIO Data (4 Bytes) SDIO Data (B Bytes) SDIO Data (B Bytes)
SDIO Data
((L – 4) mod B)
Block Basis mode
When CRC error occurs in transmission, the Type-A Transport packet is re-read
Byte Basis mode
Data (B Bytes) Data (B Bytes)