Indy R1000 Datasheet - Impinj

Indy R1000 ® Electrical, Mechanical, & Thermal Specification
6.1 Serial Interface
The serial interface has four channels: one going to the Indy R1000 reader chip (R2T) and three coming from the Indy R1000 reader chip (T2R).
Each direction has its own clock and frame synch signals (R2T_CLK, T2R_CLK and T2R_FRM, R2T_FRM). The channels are denoted as T2R_D0
and R2T_D0-2.
The data is transferred in 32-bit frames delimited with the frame synchronization signal. The data is sent most significant bit (MSB) first, and the
frame synchronization must occur one bit period before the MSB of the frame. When data is transferred from the Indy R1000 reader chip (read
request), it is placed on the lowest channel available. Up to 16 read responses can be queued in the Indy R1000 reader chip. The format of the data
frame is shown in Figure 12.
A W Rank Address Data
Figure 12: Serial Interface Frame Format
The A parameter determines if this access is valid or if it is an empty frame. The W parameter is set if the frame is a write operation. For T2R, this
value is always zero. If the same source is read several times, the rank parameter determines the order of the incoming frames. For R2T transfers,
this value is always zero. To perform a read request, the data field must be set to zero.
With the serial interface, there is an additional possibility of auto-reading certain registers. When this feature is enabled each time, the source register
is clocked and the value is placed as a read request in the T2R FIFO. The timing parameters for the serial interface are shown in Figure 13 and
Figure 13: Serial Interface T2R Timing
, and the timing requirements for the serial interface are specified in Figure 14: Serial Interface R2T Timing
Table 19.
T2R_CLK
T2R_FRM
T2R_D0
Bit 1 Bit 0 Bit 31
Figure 13: Serial Interface T2R Timing
26 Revision 2.3, Copyright © 2012, Impinj, Inc.
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