Phy circuit, Irda transceiver, Phy circuit irda transceiver – Zilog EZ80F916 User Manual
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eZ80F91 Modular Development Kit
User Manual
UM017010-0112
eZ80F91 Module Operational Description
24
Flash via the full system bus, which is available on the expansion inter-
face connectors.
PHY Circuit
The PHY KS8721 circuit has been extensively tested. However, for new
designs, Zilog recommends that you refer to the following documentation
on the Micrel website.
IrDA Transceiver
The eZ80F91 Mini Enet Module is shipped without an IrDA transceiver
installed. If you install an on-board transceiver, such as Zilog’s ZHX1810,
it connects to PD0 (TX), PD1 (RX) and PD2 (Shutdown, IR_SD). The
IrDA transceiver is of the LED type 870 nm Class 1. The IrDA transceiver
is accessible via the IrDA Controller attached to UART0 on the eZ80F91
device.
To save power or to use the UART0 as a console, the transceiver can be
disabled by the software or by an off-board signal when using the proper
jumper selection. The transceiver is disabled by setting PD2 (IRDA_SD)
High or by pulling the DIS_IRDA pin on the I/O connector Low. The
shutdown feature is used to save power. To enable the IrDA transceiver,
DIS_IRDA remains floating and PD2 is pulled Low.
The RxD and TxD signals on the transceiver perform the same functions
as a standard RS-232 port. However, these signals are processed as IrDA
3/16 coding pulses (sometimes called IrDA encoder/decoder pulses).
When the IrDA function is enabled, the final output to the RxD and TxD
pins are routed through the 3/16 pulse generator.