5

RAM HIGH ADDRESS jumpers:

These jumpers are for disabling some of the address lines from the

controller to the SRAM. See the External Memory Interface chapter.

RS-232 connector:

The STK503 has an on-board RS-232 converter. In order to use it, you

must connect the AVR to the AVR side of the connector, and the external

RS-232 equipment (such as a PC) to the RS-232 side. See RS-232

Driver for more information.

PORTx connectors:

All of the AVR ports are accessible on the port connectors. They are

marked with text corresponding to the name of the AVR port. In addition

to the port pins, they also have VCC and GND pins. See the Appendix for

pinout.

Mounting the STK503

First of all the STK503 must be mount on top of the STK500.

1.

Turn off power on the STK500.

2.

Remove any other top cards.

3.

Remove any devices from sockets of the STK500.

4.

Place the STK503 on STK500. Make sure the EXPAND0 and EXPAND1

headers on both cards align properly.

Figure 3-2: Mounting the STK503

Placing the AVR in the ZIF socket

The ZIF socket on STK503 takes AVRs in 100-pin TQFP packages.

To use STK500 and 100-pin AVR devices with LCD controller such as the

ATmega3290 and ATmega6490, you must use the STK504 top module, not