diff -uNr a/m/MANIFEST.TXT b/m/MANIFEST.TXT
--- a/m/MANIFEST.TXT 27a062d2599973684b8fd9888be347d9b492fc94b9b29ad776dd672b11fb49606d226ceabbe5295f72a56fec277aeb465a9072961134be60e8054fbd8a705b6d
+++ b/m/MANIFEST.TXT 0f03021ae4e766b63be5efe5cf5e672fc90202022ca05772621f5299c9b808d2c8c2439b7fa555716cb33a6adb8351e582275ffbafdf6cc633e528522343720e
@@ -1,2 +1,2 @@
-586606   m_genesis   "Genesis."
-
+586606   m_genesis                 "Genesis."
+586747   errata_slaveirq           "Fix of slave IRQ clearing."
diff -uNr a/m/mipsinst/m_instrs.asm b/m/mipsinst/m_instrs.asm
--- a/m/mipsinst/m_instrs.asm c5afa1184e847ba45411669a68d1cc0f62a2bacb17155541f525a70d4edefd9a62789675f30c1eb79621d8737674fe39ba7a5d913d30fe18e8b785f3cf48276d
+++ b/m/mipsinst/m_instrs.asm 0b4157a311317d55241b7a9700e16b0952cc540285d4922ec2d6626c29c3a9c83de29d18068d9be2a721b801cded2d930a4cdecf4991c5c2eab707e5e987bde6
@@ -470,7 +470,7 @@
 _mtc0_r13: ;  0x0d
         test    ecx,   ecx              ; Sel != 0 ?
         jnz     _mtc0_unknown           ; ... then unknown; else:
-%define CAUSEMASK ((1 << 23) | (1 << 22) | (3 << 8))
+%define CAUSEMASK ((1 << 23) | (1 << 22) | (255 << 8))
         mov     eax,        CP0_Cause   ; eax        := CP0_Cause
         and     ebx,        CAUSEMASK   ; T          := T   & CAUSEMASK
         and     eax,        ~CAUSEMASK  ; eax        := eax & ~CAUSEMASK