73S1209F Data Sheet
DS_1209F_004
CLK
IO
Data from Card
(Bit 8)
Protection Bit
(Bit 9)
Data from Card
(Bit 1)
RLength Count MAX
RLength Count
RLength = 9
Rlen=8
Rlen=0
Rlen =1
Rlen=9
RLength Interrupt
RX data
RX FIFO
(Data from Card is ready for CPU read)
Protection Bit Data
(Bit 9)
Protection Bit is ready for CPU read
TX/RX Mode Bit
TX = '1'
1._ Interrupt generated
when Rlength counter is
Max
3._ Reload RLength
counter
2._ Read and clear
Interrupt
Receive data in 9 bit mode
CLK
RLength Count
RLength = 9
RLength Count MAX
Rlen=9
Rlen=8
RLength Interrupt
CLK Stop
CLK Stop Level = 0
2._Stop CLK after the last
byte and protection bit
1._ Interrupt generated
when Rlength counter is Max
Stop CLK after receiving the last byte and protection bit.
Figure 23: Operation of 9-bit Mode in Sync Mode
Synchronous card operation is broken down into three primary types. These are commonly referred to as
2-wire, 3-wire and I2C synchronous cards. Each card type requires different control and timing and
therefore requires different algorithms to access. Teridian has created an application note to provide
detailed algorithms for each card type. Refer to the application note titled 73S12xxF Synchronous Card
Design Application Note.
78
Rev. 1.2
TERIDIAN [ TERIDIAN SEMICONDUCTOR CORPORATION ]
