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ZBasic Language Reference 193 ZX Microcontroller Family Appendix J - ZX-32a4 Hardware Reference The ZX-32a4 device utilizes the 44-pin TQFP package version of the Atmel AVR ATxmega32A4 microcontroller that has been programmed with a special ZX control program. In order to use the ZX- 32a4 you must supply several additional components as described below. In each of the diagrams presented below, only a portion of the ZX pins is shown. Those that are not germane to the circuit being discussed are omitted for clarity. J.1 ZX-32a4 Specifications The electrical specifications of the ZX-32a4 are exactly those of the ATxmega32A4. Rather than reproducing them here the reader is directed to the datasheet published by Atmel. It can be obtained from the Atmel website |http://www.atmel.com or from the ZBasic website |http://www.zbasic.net. J.2 ZX-32a4 Required External Components The circuits described below represent the minimum external circuitry required to operate the ZX-32a4. Depending on your application, you may need additional circuitry to take advantage of the capabilities of the ZX-32a4 series device. In contrast to some other ZX devices, the ZX-32a4 devices do not require an external EEPROM for program storage. Rather, the compiled user program is stored in the ZX’s internal Flash memory. The maximum user program size is 32K. Power Source The ZX-32a4 needs a regulated voltage source capable of providing at least 200mA of current. The ZX- 32a4n will operate reliably with a supply voltage between 2.6 volts and 3.6 volts. A recommended circuit is shown below. A suitable heatsink will probably be required in most cases to keep the regulator IC below its maximum operating temperature. Consult the regulator datasheet for more information. ZX-32a4 Power Source If you do not plan to use the Analog-to-Digital converter channels you can eliminate the inductor and the capacitor on the right side of the diagram. In this case, pin 39 would be connected directly to the power source (same as pins 9, 19 and 31). Although not shown on this diagram, the ground pins of the ZX-32a4 (pins 8, 18, 30 and 38) must be connected to the common ground of the system.