AT90CAN128 CAN网关方案

Atmel公司的AT90CAN128 是8位带有128B ISP Flash和CAN控制器的微控制器，它采用AVR增强型RISC架构，有丰富的指令集和32个通用的工作寄存器，吞吐量达到1 MIPS /MHz，广泛应用于汽车电子，工业控制以及家庭网关等。本文介绍了AT90CAN128的主要性能，方框图以及用于汽车网关的开发板ATAVRAUTO100的主要性能与详细电路图。

AT90CAN128 8-bit Microcontroller with 128K Bytes of ISP Flash and CAN Controller

The AT90CAN32/64/128 is a low-power CMOS 8-bit microcontroller based on the AVR
enhanced RISC architecture. By executing powerful instructions in a single clock cycle, the AT90CAN32/64/128 achieves throughputs approaching 1 MIPS per MHz allowing the system designer to optimize power consumption versus processing speed.

The AVR core combines a rich instruction set with 32 general purpose working registers. All 32 registers are directly connected to the Arithmetic Logic Unit (ALU), allowing two independent registers to be accessed in one single instruction executed in one clock cycle. The resulting architecture is more code efficient while achieving throughputs up to ten times faster than conventional CISC microcontrollers.

The AT90CAN32/64/128 provides the following features: 32K/64K/128K bytes of In-System Programmable Flash with Read-While-Write capabilities, 1K/2K/4K bytes EEPROM, 2K/4K/4K bytes SRAM, 53 general purpose I/O lines, 32 general purpose working registers, a CAN controller, Real Time Counter (RTC), four flexible Timer/Counters with compare modes and PWM, 2 USARTs, a byte oriented Two-wire Serial Interface, an 8-channel 10-bit ADC with optional differential input stage with programmable gain, a programmable Watchdog Timer with Internal Oscillator, an SPI serial port, IEEE std. 1149.1 compliant JTAG test interface, also used for accessing the On-chip Debug system and programming and five software selectable power saving modes.

主要特性：
High-performance, Low-power AVR® 8-bit Microcontroller
Advanced RISC Architecture
133 Powerful Instructions – Most Single Clock Cycle Execution
32 x 8 General Purpose Working Registers + Peripheral Control Registers
Fully Static Operation
Up to 16 MIPS Throughput at 16 MHz
On-chip 2-cycle Multiplier
Non volatile Program and Data Memories
32K/64K/128K Bytes of In-System Reprogrammable Flash (AT90CAN32/64/128)
Endurance: 10,000 Write/Erase Cycles
Optional Boot Code Section with Independent Lock Bits
Selectable Boot Size: 1K Bytes, 2K Bytes, 4K Bytes or 8K Bytes
In-System Programming by On-Chip Boot Program (CAN, UART, ...)
True Read-While-Write Operation
1K/2K/4K Bytes EEPROM (Endurance: 100,000 Write/Erase Cycles) (AT90CAN32/64/128)
2K/4K/4K Bytes Internal SRAM (AT90CAN32/64/128)
Up to 64K Bytes Optional External Memory Space
Programming Lock for Software Security
JTAG (IEEE std. 1149.1 Compliant) Interface
Boundary-scan Capabilities According to the JTAG Standard
Programming Flash (Hardware ISP), EEPROM, Lock & Fuse Bits
Extensive On-chip Debug Support
CAN Controller 2.0A & 2.0B - ISO 16845 Certified (1)
15 Full Message Objects with Separate Identifier Tags and Masks
Transmit, Receive, Automatic Reply and Frame Buffer Receive Modes
1Mbits/s Maximum Transfer Rate at 8 MHz
Time stamping, TTC & Listening Mode (Spying or Autobaud)
Peripheral Features
Programmable Watchdog Timer with On-chip Oscillator
8-bit Synchronous Timer/Counter-0
10-bit Prescaler
External Event Counter
Output Compare or 8-bit PWM Output
8-bit Asynchronous Timer/Counter-2
10-bit Prescaler
External Event Counter
Output Compare or 8-Bit PWM Output
32Khz Oscillator for RTC Operation
Dual 16-bit Synchronous Timer/Counters-1 & 3
10-bit Prescaler
Input Capture with Noise Canceler
External Event Counter
3-Output Compare or 16-Bit PWM Output
Output Compare Modulation
8-channel, 10-bit SAR ADC
8 Single-ended Channels
7 Differential Channels
2 Differential Channels With Programmable Gain at 1x, 10x, or 200x
On-chip Analog Comparator
Byte-oriented Two-wire Serial Interface
Dual Programmable Serial USART
Master/Slave SPI Serial Interface
Programming Flash (Hardware ISP)
Special Microcontroller Features
Power-on Reset and Programmable Brown-out Detection
Internal Calibrated RC Oscillator
8 External Interrupt Sources
5 Sleep Modes: Idle, ADC Noise Reduction, Power-save, Power-down & Standby
Software Selectable Clock Frequency
Global Pull-up Disable
I/O and Packages
53 Programmable I/O Lines
64-lead TQFP and 64-lead QFN
Operating Voltages: 2.7 - 5.5V
Operating temperature: Automotive (-40°C to +125°C)
Maximum Frequency: 8 MHz at 2.7V, 16 MHz at 4.5V

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图1. AT90CAN128方框图

AT90CAN128开发板ATAVRAUTO100
This board includes all elements necessary for designers to quickly develop code related to CAN and LIN communication gateway implementing the AT90CAN128 and for prototyping and testing
of new designs.

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图2. ATAVRAUTO100外形图
The ATAVRAUTO100 provides the following features:
AT90CAN128 QFN64,
AVR Studio software interface ,
Power supply:
regulated 5.0V out of the VBAT (typical 12V) from the LIN connector
JTAG connector:
for on-chip In Situ Programming (ISP)
for on-chip debugging using JTAG ICE
Serial interfaces:
1 CAN interface (High Speed and Low Speed)
1 LIN interface 1.3 and 2.0 compliant (Software library available on the Atmel website for LIN 1.3).
On-board resources:
1 high speed CAN transceiver ATA6660
1 LIN transceiver ATA6621 implementing one 5.0V voltage regulator and a watchdog
1 blue LED
1 Jumper to add a 1Kpull-up resistor when Master mode is selected (LIN)
On-board In Situ Programming jumper
System clock:
8 MHz crystal
Dimension: 45 mm x 45 mm

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图3.ATAVRAUTO100 开发板电路图

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上表位ATAVRAUTO100 开发板所用材料清单