EZ80F91MCU ZILOG [Zilog, Inc.], EZ80F91MCU Datasheet - Page 226

• Manufacturer Part Number: EZ80F91MCU
• Description: eZ80Acclaim-TM Flash Microcontrollers
• Manufacturer: ZILOG [Zilog, Inc.]

Table 109. GPIO Mode Selection when using the IrDA Encoder/Decoder
PS019209-0504
GPIO Port D
Bits
PD0
PD1
PD2–PD7
Loopback Testing
interrupt sources. Recommended GPIO Port D control register settings are pro-
vided in Table 109. Refer to the section covering the
put, on page 58 for additional information on setting the GPIO Port modes.
Both internal and external loopback testing can be accomplished with the endec
on the eZ80F91 device. Internal loopback testing is enabled by setting the
LOOP_BACK bit to 1. During internal loopback, the IR_TxD output signal is
inverted and connected on-chip to the IR_RxD input. External loopback testing of
the off-chip IrDA transceiver can be accomplished by transmitting data from the
UART while the receiver is enabled (IR_RxEN set to 1).
Infrared Encoder/Decoder Register
After a RESET, the Infrared Encoder/Decoder Register is set to its default value.
Any Writes to unused register bits are ignored and reads return a value of 0. The
IR_CTL register is described in Table 110.
Table 110. Infrared Encoder/Decoder Control Registers
(IR_CTL = 00BFh)
Allowable GPIO
Port Mode
7
7
Any other than GPIO Mode 7
(1, 2, 3, 4, 5, 6, 8, or 9)
Bit
Reset
CPU Access
Note: R = Read only; R/W = Read/Write.
Bit
Position
[7:3]
Value
00000
Description
Reserved.
P R E L I M I N A R Y
R
7
0
Allowable Port Mode Functions
Alternate Function
Alternate Function
Output, Input, Open-Drain, Open-Source, Level-
sensitive Interrupt Input, or Edge-Triggered Interrupt
Input
R
6
0
R
5
0
R
4
0
General-Purpose Input/Out-
R
3
0
Product Specification
Infrared Encoder/Decoder
R/W
2
0
eZ80F91 MCU
R/W
1
0
R/W
0
0
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