PS026102-1207

Onboard Component Description

Product Specification

16

disabled by setting PD2 (IR_SD) High or by pulling the DIS_IRDA pin on the I/O

connector Low. The shutdown is used for power savings. To enable the IrDA transceiver,

DIS_IRDA is left floating and PD2 is set to Low.

Reset Generator

The onboard Reset Generator Chip performs reliable Power-On Reset. The chip generates

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 components or for resetting the Zdots with a low-impedance output

(for example, a 100

Ω push button).

Serial Interface Ports

The CPU contains two UARTs with programmable baud rate generators. UART0 is con-

nected to GPIO PD[0:7] on the I/O connector. UART1 is connected to GPIO PC[0:7] on

the I/O connector.

Do not connect an RS-232 interface without level shifters. There are no

RS-232 level shifters on the Zdots.

Physical Dimensions

The footprint of the Zdots PCB is 63.5 mm x 78.7 cm. With an RJ-45 Ethernet connector,

the overall height is 25 mm, see Figure 5 on page 17.

Note: