Privat and global regiters testing routine. The testing pattern is walking 1 and 0,
prepared once by shifting of 0 (1) and then by using multiplication.
Prf[i] and grf[i] are compared, after being initialized in the same manner. The
block of privat constants represents the result from the test, as follows:

0xC00   error indicator for r0 -g0 pare,    0, if no error
0xC01   error indicator for r1 -g1 pare,    0, if no error
0xC02   error indicator for r2 -g2 pare,    0, if no error
0xC03   error indicator for r3 -g3 pare,    0, if no error
0xC08   error indicator for r4 -g4 pare,    0, if no error
0xC09   error indicator for r5 -g5 pare,    0, if no error
0xC0A   error indicator for r6 -g6 pare,    0, if no error
0xC0B   error indicator for r7 -g7 pare,    0, if no error
0xC10   error indicator for r8 -g8 pare,    0, if no error
0xC11   error indicator for r9 -g9 pare,    0, if no error
0xC12   error indicator for r10 -g10 pare,  0, if no error
0xC13   error indicator for r11 -g11 pare,  0, if no error
0xC18   error indicator for r12 -g12 pare,  0, if no error
0xC19   error indicator for r13 -g13 pare,  0, if no error
0xC1A   error indicator for r14 -g14 pare,  0, if no error
0xC1B   error indicator for r15 -g15 pare,  0, if no error