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ZBasic Language Reference 197 ZX Microcontroller Family Appendix K - ZX-128a1 Hardware Reference The ZX-128a1 device utilizes the 100-pin TQFP package version of the Atmel AVR ATxmega128A1 microcontroller that has been programmed with a special ZX control program. In order to use the ZX- 128a1 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. K.1 ZX-128a1 Specifications The electrical specifications of the ZX-128a1 are exactly those of the ATxmega128A1. 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. K.2 ZX-128a1 Required External Components The circuits described below represent the minimum external circuitry required to operate the ZX-128a1. Depending on your application, you may need additional circuitry to take advantage of the capabilities of the ZX-128a1 series device. In contrast to some other ZX devices, the ZX-128a1 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 128K. Power Source The ZX-128a1 needs a regulated voltage source capable of providing at least 200mA of current. The ZX- 128a1n 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-128a1 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, pins 4 and 94 would be connected directly to the power source (same as pins 4, 24, etc.). Although not shown on this diagram, the ground pins of the ZX- 128a1 (pins 3, 13, 23, 33, 43, 53, 63, 73, 84, 93) must be connected to the common ground of the system.