Dev Kits Ease Automotive System Development

According to Wikipedia, today’s cars contain up to 100 electronic control units (ECUs) and even commercial vehicles may have 40 or so. These control units are found in engine management, automatic transmission, anti-lock braking, infotainment, lighting, alarms and immobilisers, climate control, electric windows and hatches, parking aids and, of course, external communications – both cellular and GPS.

There are some useful development kits available to help automotive system designers develop systems faster. Here are a few examples.

 

Remote Keyless Entry/Passive Entry Passive Start

Standard for most vehicle designs today, remote keyless entry (RKE) systems allow vehicles to be unlocked wirelessly when the driver presses a button on their key fob. Passive entry/passive start (PEPS) is becoming more popular for high-end vehicles: similar to RKE, it also uses RF communication, but takes it a step further. With PEPS the driver can simply touch the car door to unlock it, and press a start button on the dashboard to start the engine, as the car communicates with the key in his or her pocket.

Figure 1: Atmel’s ATAK51003-V1 Development Kit is designed especially for remote keyless entry
and passive entry/passive start applications.

Both these applications demand very low power operation for the battery-powered key, plus support for the AES-128 cryptography standard to protect transmissions between the car and the key. Atmel offers a reference design/development kit for car access designs, incorporating RKE, PEPS and immobiliser applications, the ATAK51003-V1. The design is based on the ATA5791 8-bit microcontroller, which includes an RF transmitter and is designed especially for automotive key fobs. It features an integrated hardware AES-128 encryption engine, and its current consumption when listening is just 4.7 µA, helping the key’s battery last as long as possible.

 

Car Alarm

All cars these days come with an alarm to help guard against theft of the vehicle, and theft of property from inside it. A basic car alarm system might look something like the block diagram below, with a microcontroller connected to a battery to power itself, a tilt sensor to tell if the car is being moved, the horn to sound the alarm, and communicating via a CAN or LIN bus to tell other vehicle systems that the car is being stolen so that other preventative actions may be taken (perhaps immobilisation).

                                                                   Figure 1:

Figure 2: A basic block diagram for a car alarm system that uses the
car’s horn to sound the alarm.

STMicroelectronics’ 8-bit STM8A series of automotive microcontrollers is perfectly placed for applications like car alarm systems. In the series, the STM8AL is the very low power part, while the STM8AF has more memory. The STM8A Discovery development kit is designed to show off the features of both devices. It comprises two boards that can be connected via LIN – the STM8AF board can do CAN and LIN, but the STM8AL board is a LIN slave only.

Figure 3: STMicroelectronics’ STM8A Discovery kit is a quick way to get started
with its automotive 8-bit microcontrollers
.

 

Instrument Cluster

The instrument cluster in the dashboard is the main user interface communicating essential information to the driver. This information may be displayed by gauges - like the speedometer or fuel level, or LCD segment displays - like the time or ambient temperature. Although some instrument cluster displays rely solely on LCDs, displaying the information digitally does not offer the same feedback to the driver as the needle of a gauge does, so both technologies are still vitally important.

Figure 4: A block diagram for an instrument cluster design based on a
Microchip PIC 16/18/24 microcontroller.

Microchip’s PICDEM LCD2 Demonstration Board (DM163030), which uses a PIC18 device, includes an LED voltage booster and contrast controller alongside a sample LCD for prototyping. The PIC18 microcontroller has a variety of on-chip peripherals that suit it to instrument clusters. Performance is sufficient to support Zero Position Detect for stepper motor controlled gauges, while on-chip PWMs can be used for micro-stepping.

 

Radar for ADAS

Advanced Driver Assistance Systems (ADAS) are designed to help prevent accidents and maintain road safety under difficult conditions. Systems under development use sophisticated processors to interpret image data from multiple cameras and alert the driver to any potential collisions, and/or apply the brakes. ADAS include sub-systems that may take the controls in certain situations, so it’s therefore essential that the highest levels of safety and security are met.

Figure 5: TI’s Hercules Development kit is suitable for developing applications that will require ISO 26262 certification as it has advanced functional safety features.

As an example, for developing a radar system to alert drivers of potential collision situations, TI recommends the Hercules Development Kit. This kit is for safety-critical systems, featuring the Hercules microcontroller platform, which uses core functional safety techniques to speed up ISO 26262 certification. The kit features the TMS570 microcontroller and is sophisticated enough to be used to develop fully-fledged applications.