Current Bugs LSM (versions 2  and 3 )

Am I ever going to update LSM?

The quick answer is no. I don't get paid for this anymore. I have looked into Windows32 programming in detail and decided it is not worth it. The multitasking operating system will require considerable work to ensure reliable for real time stimulus generation with commercial hardware.

• LSM cannot consistently set all video boards to 256-color mode. Most video boards now only use direct color mode (24 or 32 bits/per pixel). The video boards listed on the LSM home page are the only boards that I know of that handle 256 color mode well. This situation is unlikely to improve since the VBE standard will be phased out for that "oh, so great" DIRECTX. If you want a compatible board look for one that VESA VBE 3.0 compilant.
  
  
• "Page flipping" may not work on all video cards and page flipping is limited to on-board video memory only. In VBE 3.0 or higher, the page flipping occurs after a vertical refresh. If your board uses VBE 2.0 or lower then you need a bug fix. Contact me for another version of LSM. This is particularly true of ATI video cards. The software actually calls a VESA BIOS function of a vertical scroll (interrupt 10h; ax = 4F07h, bx = 80h, cx = 00h, dx = offset factor * bank). I found this BIOS call to be more consistently implemented across video boards. The drawback is improper page flipping if the user sets custom front and back vertical porches (e.g. to change vertical frame timing). I can perform BitBLT swapping of memory to video memory, but it is too slow!
  
  
• Currently there is no provision for pure luminance modulation. For instance, you want to modulate the intensity of a bright white line on a completely black background. This method is avoided since the mean luminance of the stimulus is changing. It is completely feasible to program LSM to do this, but I have not seen a reason yet to do so
  
  
• There is no error checking for spatial frequency sweeping. Since LSM uses 256-color mode, the spatial frequency sweep must be an sub-multiple of the spatial period. You can set LSM to do a very slow spatial frequency sweep but the spatial pattern will have "uneven interruptions" or asymmetry. The best solution is to set the spatial sweep factor to 0.5 (octave steps downward) and set the spatial period to an even number with the most octave steps (i.e., 248).
  
   
• Bitmap files are limited to PCX (ver 5) format only. I have code for reading Windows ".bmp" format but I have no plans to implement  it.

Bug Fixes and new additions.

• Version 3.0d (3/3/2004) corrected a serious flaw in trigger timing. When the user used the mouse (or joystick) to pause a series of Epochs, the trigger was not restarted even though the stimulus cycle was. If you were using the LPT port for as a TTL trigger and then paused the stimulus, the triggering could be offset from the start of the stimulus.
•  Version 3.0c corrected a bug in Triggering, LSM triggering was out of synch of the stimulus by one video frame, usually before the start of the temporal cycle.  The problem was that the program waited until the end of the trigger cycle period to output a trigger. Hence, the trigger was one frame BEFORE the expected start of the stimulus timing cycle.
•  Version 3.0a corrected the clipping of standard bit maps after implementation of video page offset.
• Version 3.0a adds the ability to move a bitmap in the video screen by either an ascii file with (x, y) values or by mouse.
• Version 3.0a added option to wait for an input trigger to the LPT port before starting the stimulus generation.
• Version 3.0a added more options for video frame timing for the luminance calibration (CalibRGB.exe).
• Version 3.0a corrected the bug that prevented chaining of multiple stimulus files.
• Version 2.0a corrects the PCX timing parameter that wasn't saved in the configuration files.
• Version 2.0a adds "sticky" submenus.
• Added a parameter to increase the trigger pulse length by placing a number from 0 (shortest) to 255 (longest) on the third line of the LSM.INI file. Edit the file with NOTEPAD or any other text editor. Each increment in time is dependent upon your machine's speed.
• Version 2.0 implements many new changes in simple menus, separate bitmap manipulation, etc.
• Fixed bug in reading files that failed to reset Background "on/off" and "random" starting contrast. (5/14/01)
• "Glizty" start-up configuration demonstrates simultaneous sweep in color, of a color grating of changing spatial frequency on top of a PCX bitmap (s.f. sweep is slow, which is inappropriate for the spatial period) (ver 1.2f).
• If the screen resolution doesn't change, LSM now continually loops through stimulus file(s) without resetting the graphics mode (ver 1.2f).
• Corrected bug that wouldn't allow user to load up a spatial function by text file (ver 1.2f).
• Improved lock-up problems and added more options with the Calibration program 'Calibrgb.exe' (Ver 1.2f)
• improved lock-up with random dot example (ver 1.2e)
• plots the raw data of current calibration file (ver 1.2e)
• fixed bug with randomization of color vectors for 2-alternative forced choice (ver. 1.2e)
• improved timing between trials for 2-alternative forced choice (ver. 1.2e)
• Increased the possible number of drift values in an ASCII text file to 2048 directions (ver. 1.2d)
• Added a screen "blanking box" at the bottom left of the screen in any menu screen, so that the user can black out the screen while not working (ver. 1.2c)
• Manually enter in values for the luminance calibration program / corrects the check on calibration data (ver. 1.2c)
• fixes bugs that left files open after loading files from the disk. (ver. 1.2a)
• corrected the SF_Sweep demo configuration file (ver. 1.2)
• corrected extra video frame between page flipping for multiple PCX files, still needs fixing for speed (ver. 1.2)
• Correctly runs through chained stimulus files / add arbitrary drift option (ver. 1.2)
• incorporates compatibility with Matrox video setup for DOS (VBESETUP and VBETSR) (ver. 1.2)
• corrected triggering (ver. 1.2)
• add comments during a test run in alternative forced choice program (ver. 1.1)
• Fixed pixel clock bug on screen timing program "VARYH&V" (ver. 1.1)
• fixed bug  generating a screen with arbitrary spatial waveform (ver. 1.1)
• Implemented multiple page flipping for multiple PCX files. This is helpful for dynamic random dot stereo.
• better input routine (ver. 1.1)

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