The ZX-128a4U is a "native mode" ZX device based on one of the new Atmel xmega processors.
Since it is largely source code compatible with the other 44-pin ZX devices, it provides
an excellent upgrade path for more demanding applications.
The heart of the ZX-128a4U is the Atmel AVR ATxmega128a4U microcontroller running at 29.5MHz which provides 8192 bytes
of RAM, 2016 bytes of EEPROM and 128K of internal Flash memory for your programs.
The xmega128a4U has other resources available to your program including five high-speed serial ports,
analog-to-digital converters, digital-to-analog converters, timers and other sub-systems that may be accessed using
routines in the ZBasic System Library. Alternately, some of these resources may be accessed
directly using built-in registers.
You may download a schematic with suggested support circuitry for the ZX-128a4U (identical to that for the ZX-32a4) as a PDF.
ZX-128a4U Technical Features¹
| Package |
44-pin TQFP |
| Operating Temperature |
-40 to +85°C |
| Processor |
Atmel AVR ATxmega128a4U |
| Power Requirements |
2.6-3.6VDC regulated |
| Processor Speed |
Up to 29.5MIPS (29.5MHz) |
| Program Execution Speed |
Up to 5.8 million instructions/sec² |
| User RAM |
8K bytes |
| Non-volatile Data Memory |
2016 bytes |
| Program Memory |
128K bytes |
| Digital I/O pins |
30+2³ |
| Analog-to-Digital Channels |
Up to 12 channels, 12-bit resolution |
| Digital-to-Analog Channels |
Up to 2 channels, 12-bit resolution |
| PWM Channels |
Twelve 16 bit (four timers) |
| I2C Support |
1 HW channel, 4 SW channels |
| 1-Wire Support |
Bit and byte level |
| SPI Support |
4 HW channels |
| Synchronous Serial I/O Support |
1-16 bits, MSB or LSB first |
| Asynchronous Serial I/O Ports |
5-HW, up to 4 SW full duplex |
| X-10 Command Support |
Yes |
| Multi-tasking Support |
Yes |
| Pin Change Interrupts |
All I/O lines |
| Analog Comparator Interrupt |
Yes |
| Interval Timer |
Yes |
| Exception Handling Support |
Yes |
| Floating Point Math |
Yes - IEEE 32-bit |
| Advanced Floating Point
Functions (sin, cos, log, etc.) |
Yes |
| Programming Interface |
Serial - 115.2K baud |
| Field Upgradeable System Software |
No |
| Supports Inline Assembly Code |
Yes |
| Supports Interrupt Handling Code |
Yes |
Notes:
1) Items in boldface indicate differences from the ZX-32a4.
2) Speed based on the instruction b = b + 1.
3) The additional 2 I/O lines dedicated for serial I/O.
Specifications subject to correction and change without notice.
|
A standard serial port is required to download code to the ZX-128a4U.
If your computer does not have a standard 9-pin serial port but does have a USB port, you may use a USB to serial adapter.
Note, however, that some USB to serial adapters are too slow to be useful with the ZX microcontrollers.
We have found that adapters based on the second generation FTDI chips seem to work well.
The ZBasic IDE, compiler and documentation may be obtained free of charge via the Download page. See the menu at the left.
