The XE166 16-bit real-time signal controller (RTSC) delivers substantial speed gain, propelling 16-bit microcontrollers into the 32-bit league. The outstanding real-time performance is due to fast interrupt response times, rapid context switching, and the addition of two more local register banks. It incorporates an MCU that unites the strengths of a 16-bit C166 core for peripheral control with the high computing power of a DSP. Clocked at 80MHz and capable of executing instructions in a single clock cycle, the XE166 chip delivers 80MIPS – twice the performance of its predecessor. It has three times the memory capacity – up to 768KB.
Besides substantially expanding the flash memory, it also features a highly effective error correction (ECC), capable of correcting single-bit errors and detecting double-bit errors. The significantly enlarged RAM (up to 82KB) consists of 2KB of dual-port RAM, up to 16KB of data SRAM, and as much as 64KB of program and data SRAM. It also has two synchronized AD converters with up to 24 channels, 10-bit resolution (+/- 2 LSB), and a conversion time of less than 1.2µs. Tightly coupled with the PWM units (CCU6E), the high-precision AD converters can be used to control up to four motors. The XE166 microcontroller offers a wide variety of interface options. A MultiCAN interface, for example, supports up to five independent CAN nodes and a maximum of 128 message objects. This enables, say, a FIFO or a CAN gateway to be implemented with ease, and is a valuable capability, given that complex applications often need intelligent network communication.
It can also incorporate up to three Universal Serial Interface Channel (USIC) modules, each of which is a cluster of two identical USIC channels, providing six USIC channels in total. The channels are flexible and can be used to connect external peripherals over Universal Asynchronous Receiver Transmit (UART) and Local Interconnect Network (LIN) interfaces, Serial Peripheral Interfaces (SPI), Inter-IC (IIC) bus, and Inter-IC Sound (IIS) interfaces. Every channel (and the baud rate generation) can be configured independently.
The architecture includes special mechanisms to enable rapid responses to internal and external service requests sent to the microcontroller. These include a DMA transfer issued by the PEC; an interrupt system with up to 87 sources and selectable external inputs for interrupt generation; 16 interrupt priority levels, each with eight prioritization groups; and extremely short interrupt response times.
The PEC allows data to be transferred between the memory and peripherals in just a single clock cycle, without requiring the intervention of an interrupt service routine. It does this by providing eight service channels over which a single byte or word can be transferred, plus the option of being able to update source and target pointers automatically. A PEC transfer can be triggered by an internal interrupt service request and offers the fastest possible interrupt response time.
The microcontroller is suited for high-efficiency control systems for inverters and voltage converters. It enables energy-efficient solutions in the transportation sector – in locomotives, streetcars, buses, and agricultural machinery, for example – as well as in the renewable energy sector (in solar, fuel cell, and wind power generating systems). With its fast interrupt timing and flexible PWM generation, it can be used to control anything from small machines to the high-voltage motors capable of replacing conventional hydraulic systems. |
