Z8 Encore!® Motor Control Flash MCUs
Product Specification
146
to the UART. Communication is half-duplex, which means simultaneous data transmis-
sion and reception is not allowed.
The baud rate is set by the UART’s Baud Rate Generator and supports IrDA standard baud
rates from 9600 baud to 115.2 Kbaud. Higher baud rates are possible, but do not meet
IrDA specifications. The UART must be enabled to use the infrared endec. The infrared
endec data rate is calculated using the following equation:
System Clock Frequency (Hz)
Infrared Data Rate (bits/s) =
16 x UART Baud Rate Divisor Value
Transmitting IrDA Data
The data to be transmitted using the infrared transceiver is first sent to the UART. The
UART’s transmit signal (TXD) and baud rate clock are used by the IrDA to generate the
modulation signal (IR_TXD) that drives the infrared transceiver. Each UART/Infrared
data bit is 16-clocks wide. If the data to be transmitted is 1, the IR_TXD signal remains
Low for the full 16-clock period. If the data to be transmitted is 0, a 3-clock high pulse is
output following a 7-clock low period. After the 3-clock high pulse, a 6-clock low pulse is
output to complete the full 16-clock data period. Figure 20 illustrates IrDA data transmis-
sion. When the infrared endec is enabled, the UART’s TXD signal is internal to the
Z8FMC16100 Series Flash MCU while the IR_TXD signal is output through the TXDpin.
16-Clock
Period
Baud Rate
Clock
UART’s
TxD
Start Bit = 0
Data Bit 0 = 1
Data Bit 1 = 0
Data Bit 2 = 1
Data Bit 3 = 1
3-Clock
Pulse
IR_TxD
7-Clock
Delay
Figure 20. Infrared Data Transmission
Infrared Encoder/Decoder
P R E L I M I N A R Y
PS024604-1005
ZILOG [ ZILOG, INC. ]
