73S1209F Maxim, 73S1209F Datasheet - Page 77

• Manufacturer Part Number: 73S1209F
• Description: The 73S1209F is a self-contained, SoC smart card reader IC that is an ideal solution for serially connected ISO 7816 design
• Manufacturer: Maxim

DS_1209F_004
Rev. 1.2
RLength Interrupt
1. Interrupt generated when Rlength counter is MAX.
2. Read and clear Interrupt.
3. Set CLK Stop and CLK Stop level high, set IO Bit low and IODir = Output.
4. Set IO Bit High and IODir = Output.
5. Set TX/RX Bit to RX mode.
6. Reload Rlength Counter.
7. Clear CLK Stop and CLK Stop level.
CLK Stop Level
RLength Count
TX/RX Mode Bit
(Rlength = 9)
TX = '1'
Figure 21: Creation of Synchronous Clock Start/Stop Mode Start Bit in Sync Mode
Figure 22: Creation of Synchronous Clock Start/Stop Mode Stop Bit in Sync Mode
1. Interrupt generated when Rlength counter is MAX.
2. Read and clear Interrupt.
3. Set CLK Stop and CLK Stop level high in Interrupt routine.
4. Set TX/RX Bit to TX mode.
5. Reload Rlength Counter.
6. Set IO Bit low and IODir = Output. Since Rlen=(MAX or 0) and TX/RX =1, IO pin is controlled by IO bit.
7. Clear CLK Stop and CLK Stop level.
Note: Data in TX fifo should not be Empty here.
CLK Stop
RLength Count - was set for length of ATR
RLength Interrupt
IODir Bit
IO Bit
CLK Stop Level
TX/RX Mode Bit
generate the start bit insertion in Synchronous mode for Synchronous Clock Start/Stop Mode protocol.
CLK
IO
TX = '1'
Synchronous Clock Start/Stop Mode style Start bit procedure. This procedure should be used to
CLK Stop
IODir Bit
Synchronous Clock Start/Stop Mode Stop bit procedure. This procedure should be used to
IO Bit
CLK
I2CMode = 1: Data to/from Card
I2CMode = 0: Data from TX fifo
IO
Data from Card -end of ATR
generate the Stop bit in Synchronous Mode.
1
RLength Count MAX
I2CMode = 1:ACK Bit (to/from card)
2
1
I2CMode = 0: Data from TX fifo
Count MAX
RLength
3
2
3
4
5
6
6
RLen=0
7
Rlen=1
Data from TX FIFO
4
START Bit
STOP Bit
73S1209F Data Sheet
5
6
Min ½ ETU
7
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