FAST IR
The following is a description of the top level
connection for the Fast IR block in the
FDC37C93xFR. Refer to the Infrared
Communications Controller Specification for
more information on Fast IR.
and the other has a second read data pin
(IRR3). The FDC37C93xFR has two pins that
can be used for these signals. These are Pins
19 and 120, which have IR Mode and IRR3 as
their second and third alternate functions,
respectively. Table 37 illustrates the selection of
the function of each of these GPI/O pins.
There are two types of modules used for Fast
IR: one has a mode pin (IR Mode) to control it,
Table 37 - Pin 19 and 120 Function Selection
PIN 19, GP40
BITS [4:3]
PIN 120, GP54
BITS [4:3]
00 MEDIA_ID1
01 GPI/O
00 nROMCS
01 GPI/O
10 IR Mode (Output)
11 IRR3 (Input)
10 IR Mode (Output)
11 IRR3 (Input)
The selection of either IRR3 or IR Mode is
performed via the HPMODE bit as follows: If
IRR3 is to be used, i.e., either (GP40 bits [4:3]
11) or (GP54 bits [4:3] =11), then HPMODE =
1. Otherwise, HPMODE =0 (IR Mode).
used, i.e., (GP40 bits [4:3] = 11) then FRX_SEL
= 1. Otherwise, FRX_SEL = 0 (GP54 is used).
The FAST bit is used to select Fast IR mode. If
FAST =1, Fast IR mode is selected.
The pin to be used for the IRR3 is selected via
the FRX_SEL bit as follows: If GP40 is to be
Table 38 below illustrates the selection of the
pins used for the Fast IR block.
Table 38 - Fast IR Read Data Pin Selection
CONTROL SIGNALS
INPUTS
FAST
HPMODE
FRX_SEL
RX1
RX2
0
X
1
1
X
0
1
1
X
X
0
1
RX1=RXD2
RX1=RXD2
RX1=GP54
RX1=GP40
RX2=IRRX2(GP12)
RX2=IRRX2(GP12)
RX2=GP54
RX2=GP40
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