SCTEST

Small programm for test (S)CHIP-8 emulators. If all test passed, you see
"OK" on upper left corner, else programm print ERROR and error number.
Written by Sergey Naydenov, e-mail: tronix286@rambler.ru (c) 2010

Errors:

ERROR INI
        Emulator initialization failed. When program start, all registers
        must be set to null.

ERROR BCD
        BCD instruction problems.

ERROR 0
        Problems with Fx65 instruction. Can't load zeroes from memory to 
        registers.

ERROR 1
        System font 8x5 not found. In memory at offset 000h - zeroes.

ERROR 2
        Addiction without overflow (254+1). VF register need to be set 0, 
        but after operation he still 1

ERROR 3
        After operation 254+1, register v0 need set to 255, but he does't.

ERROR 4
        Addiction with overflow (255+1). VF register must be set to 1, but 
        after operation he still 0

ERROR 5
        Wrong result after addiction operation (255+1). Must be 0.

ERROR 6
        After substraction 1-1 register VF must be 1, but he still 0.

ERROR 7
        Wrong result after 1-1 operation. Result must be 0.

ERROR 8
        Substract 0-1. VF register must be 0, but he still 1

ERROR 9
	Wrong result after 0-1 operation. Register v0 must be 255.

ERROR 10
                                 ... skip ...
	..sorry, i don't have time for writing all descriptions. Please see
        source code SCTEST.C8..

ERROR 23
       Can not restore HP48 flags (FX75/FX85 instructions).

ERROR 24
       Check FX1E (I = I + VX) buffer overflow. If buffer overflow, register 
       VF must be set to 1, otherwise 0. As a result, register VF not set to 1.
       This undocumented feature of the Chip-8 and used by Spacefight 2019! 
       game.