Zilog eZ80F92 - Manual (Page 54)

eZ80F92 Development Kit
User Manual
eZ80F92 Flash Module UM013911-0607
50
• On-chip SRAM: 8 KB
• Off-chip SRAM: 512 KB
• On-chip Flash: 128 KB
Reset Generator
The onboard Reset Generator Chip is connected to the eZ80F92 Reset
input pin. It performs reliable Power-On Reset functions, generating a
reset pulse with a duration of 200 ms if the power supply drops below
2.93 V. This reset pulse ensures that the board always starts in a defined
condition. The RESET pin on the I/O connector reflects the status of the
RESET line. It is a bidirectional pin for resetting external peripheral com-
ponents or for resetting the eZ80F92 Development Kit with a low-imped-
ance output (e.g. a 100-Ohm push button).
IrDA Transceiver
An onboard IrDA transceiver (ZiLOG ZHX1810) is connected 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 eZ80F92 device. The UART0 console and the IrDA trans-
ceiver cannot be used simultaneously.
To use the UART0 for console or to save power, 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 (IR_SD)
High or by pulling the DIS_IRDA pin on the I/O connector Low. The
shutdown feature is used for power savings. To enable the IrDA trans-
ceiver, DIS_IRDA is left floating and PD2 is set to Low.
The eZ80F92 Flash Module contains a ZiLOG IrDA transceiver that is
connected to the UART0 port. This port can be used as a wireless connec-
tion into the eZ80F92 Flash Module. The UART0 can connect to a stan-
dard RS232 port, or it can be configured to control the IrDA transceiver;