Techniques for user testing of the 68882

The steps required to develop a test program for the Motorola 68882 floating-point coprocessor, are documented, using only functional techniques. The resulting test program for the 68882 executes 550000 clock cycles and tests 2700 instructions. The functional test method, LEAD, is ideal for the user, since the program generates vectors directly from assembly language and test the 68882 just as it would be used in an application. Also, the LEAD method, used in conjunction with an emulated microprocessor, is proved to be a useful test development technique for a variety of coprocessors and peripherals. The intent of the 68882 program was to exhaustively test every register, data format and instruction. The authors conclude that absolute test coverage is probably not achievable, but the program is able to provide functional test coverage and to serve the end user by quickly responding to any application problems that arise