By calling dmstart(), the camera will begin log events. At a later time I can call dumpf() to have it write the events to a logfile on the CF card named "A:/log%03d.log", where the index increments until it finds a free one. This will help development quite a bit!
Sample boot log from my 5D Mark 2 with a thousand entries in the first three seconds:
Sat May 23 18:30:13 2009
0: 8.407 [STARTUP] ICU Firmware Version 1.0.7 ( 4.4.7 )
1: 8.460 [STARTUP] ICU Release DateTime 2008.12.17 10:53:23
2: 8.656 [SEQ] CreateSequencer (Startup, Num = 6)
3: 8.873 [SEQ] NotifyComplete (Cur = 0, 0x10000, Flag = 0x10000)
4: 10.759 [SEQ] seqEventDispatch (Startup, 0)
5: 10.841 [STARTUP] startupEntry
6: 46.583 [HPD] TOEDetectISR 0
7: 46.809 [HPD] CreateTask Master End
8: 47.929 [FIO] [EM] emSlaveChangeCBR : AUTO_POWEROFF (1)
9: 48.054 [FIO] [EM] emSlaveChangeCBR : UILOCK (0x0)
10: 77.229 [PROPST] dwNewAeModeDial = 2
....
79: 112.255 [SHTC] BathtubAddress:0x5c714000, Size:65536
....
1023: 2354.540 [GUI] GUI_GetPhotoStudioMode (0)
1024: 2354.648 [WINSYS] AnimationBmp::focused on AnimationBmp (8651172)
1025: 2354.833 [GUI] DlgMnMainSetup3 GOT_TOP_OF_CONTROL
1026: 2354.972 [GUI] GUI_GetFirmVersion(1.0.7-hudson)
1027: 2355.107 [GUI] GUI_GetPhotoStudioMode (0)
1028: 2394.531 [BmpDDev] ChangePhysicalScreen (PUB) 0x43F80008
1029: 2404.455 < GUI Lock > GUILock_TurnOnDisplay (PUB)
1030: 2404.569 < GUI Lock > GUILockTask 1
1031: 2404.608 [DISP] TurnOnDisplay (PUB) Type=0 fDisplayTurnOn=0
1032: 2404.928 [DISP] RequestNotifyBlank img=0 bmp=ff860868
1033: 2405.070 [DISP] VdInterruptHandler img=0 bmp=ff860868
1034: 2417.237 [DISP] RequestNotifyBlank img=0 bmp=ff860868
1035: 2421.782 [DISP] VdInterruptHandler img=0 bmp=ff860868
1036: 2438.110 [DISP] RequestNotifyBlank img=0 bmp=ff860868
1037: 2438.428 [DISP] VdInterruptHandler img=0 bmp=ff860868
1038: 2438.503 [DISP] RequestNotifyBlank img=ff85fac4 bmp=0
1039: 2455.142 [DISP] VdInterruptHandler img=ff85fac4 bmp=0
1040: 2455.217 [DISP] RequestNotifyBlank img=0 bmp=ff860868
1041: 2471.813 [DISP] VdInterruptHandler img=0 bmp=ff860868
1042: 2471.857 [DISP] BackLightOn
1043: 2811.696 [DL] PROP_EFIC_TEMP (155)
1044: 3006.238 [LVAE] EP_SetMovieManualExposureMode >> ON
1045: 3006.326 [LVAE] EP_SetDebugLogMode() >> DebugLogMode:0x00000001
1046: 3006.355 [LVAE] EP_SetLVAEDebugPort() >> ON
1047: 3009.000 [IMP] GetVramNumber 619
1048: 3009.026 [IMP] GetVramNumber 619