Intel unveils exhaustive test suite dedicated to new 80286 microprocessor
New Comprehensive Test Suite for Intel 80286 CPU Released
Daniel Balsom has unveiled a new test suite specifically designed for the Intel 80286 CPU, with a focus on real mode operation. This suite contains 326 instruction forms and has been tested on an original Harris N80C286-12 chip from 1986.
The test suite covers nearly 1.5 million instructions and captures detailed cycle-level behavior, recording over 32 million CPU cycle states. The coverage is improved over previous 8088 test suites due to better instruction generation methods. At present, the tests focus exclusively on 80286 real mode, with plans to expand to protected mode (also known as the "unreal mode") in the future.
These tests are particularly useful in characterizing subtle CPU behaviors such as interrupt push order differences from the 8086 and the prefetch queue filling after jumps, revealing details that might have been lost over time.
The test suite is used with the ArduinoX86 platform, which is designed to interface microcontrollers with vintage Intel CPUs for control and testing purposes. The tests aid in the development and verification of cycle-accurate emulators, specifically Daniel Balsom’s own MartyPC emulator, which targets accurate emulation of 80286 hardware.
The complete battery of tests, along with related software such as the test harness (MOO), the ArduinoX86 CPU controller, and MartyPC emulator, are openly available on GitHub under the permissive MIT license.
For those working on 80286 hardware emulation or deep CPU behavior analysis, this test suite enables cycle-accurate emulation and offers valuable insights into the CPU's intricate operation. Daniel encourages readers to share any findings about Intel's old processors, including those from other sources, with the tipsline.
Key Points - New test suite for Intel 80286 CPU by Daniel Balsom. - Focuses on real mode operation, with plans for protected mode testing in the future. - Contains 326 instruction forms and covers nearly 1.5 million instructions. - Records over 32 million CPU cycle states. - Used with ArduinoX86 platform and aids in the development of cycle-accurate emulators like MartyPC. - Openly available on GitHub under the MIT license. - Encourages sharing of findings about old Intel processors through the tipsline.
This test suite developed by Daniel Balsom is not only for the Intel 80286 CPU but also beneficial for those working on gadgets using data-and-cloud-computing technology. This suite, available on GitHub under MIT license, when used with the ArduinoX86 platform, aids in the development of technology that interfaces microcontrollers with vintage Intel CPUs for control and testing purposes.
