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VERSION 2! :D 
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What has changed?
 - Thanks to TriMesh, the gate-pin is now also used to determine in which model of
   Playstation PsNee is installed. The modchip algorithm thus can be optimized for
   optimal performance on specific Playstation revisions. This works by monitoring
   whether a clock signal is present on this pin - when there is one, the modchip is
   installed in a PU-22, PU-23 or PSOne Playstation, else it is installed in an older
   model Playstation. In this version of PsNee, nothing is actually done with this information.
 - Thanks to -again- TriMesh, NTSC support for PAL SCPH-102 Playstations is added! This uses
   the same method the OneChip modchip used for achieving this:
     1. Monitor the XLAT signal from the CD mechanism controller chip. This requires
        another connection to the Playstation. When this signal is 0, the first CD copy
        protection is passed! After this, there is another one.
     2. After this, watch the Address18-pin (pin 31) on the BIOS-chip. When this signal
        is high, this means the second CD copy protection is about to run.
     3. Wait a short time.
     4. Pull the Data2-pin (pin 15) on the BIOS-chip to 0. This effectively blocks the
        execution of the region check of the inserted disc.
     5. The Playstation plays the inserted disc and doesn't care whether it's PAL or NTSC!
     6. Release the 0 of the Data2-pin.
   To correctly output a PAL video color signal for a PAL TV on a PAL PSOne with an NTSC disc
   inserted, Pin 3 of IC502 must be grounded with an external switch. The modchip also could do
   this, although we would need a device with more pins available.
 - The outputted data signal is now "sliced up" to improve (or less distort) the tracking
   signal from the CD mechanism: later Playstations use the CD tracking signal for transmitting
   the SCEx-string to the Playstation instead of using a seperate connection, so when the modchip
   forces a 0 on the data-pin, the tracking signal also is gone temporarily. By slicing the data-
   signal up in little pieces at least some of the tracking signal remains and the Playstation can
   read discs more easily.
 - The two big for-loops are combined into one with an OR-statement describing the two conditions
   modchip should be active: when flagFirstCycle = 0 or when flagFirstCycle = 1 and the lid is opened
   and closed again. This makes code maintenance easier.
 - The pin-out of the modchip is changed slightly to be able to use an interrupt for the PAL=>NTSC
   BIOS-patch for PAL SCPH-102. Please use the revised pin-out found below with this code.
~TheFrietMan, The Netherlands
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     New in this version! V6
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A lot!
 - The PAL SCPH-102 NTSC BIOS-patch works flawlessly! For speed reasons this is implemented in bare
   AVR C. It is functionally identical to the OneChip modchip, this modchip firmware was disassembled,
   documented (available on request, but written in Dutch...) and analyzed with a logic analyzer to
   make sure PsNee works just as well.
 - The code now is segmented in functions which make the program a lot more maintable and readable
 - Timing is perfected, all discs (both backups and originals of PAL and NTSC games) now work in the
   PAL SCPH-102 test machine
 - It was found out that the gate signal doesn't havbe to be hooked up to a PAL SCPH-102 Playstation
   to circumvent the copy protection. This is not tested on other Playstation models so the signal still
   is available
 - The /xlat signal is no longer required to time the PAL SCPH-102 NTSC BIOS-patch
 - Only AVR PORTB is used for compatibility reasons (almost all the AVR chips available have PORTB)
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            AttyNeeRC3
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I just have a lot of Attiny13a and normal firmware for them was not.
 Modavr does not support stealth, and does not launch copies from NTSC disks on the slime.
 Then I came across the American firmware PsNee. It can patch bios slimki for NTSC disks.
 But it did not support Attiny13a (it exceeded the size and used the flash.h not supported in Attiny13a).
 Plus, the firmware itself was a compilation of different authors and contained a lot of garbage occupying a precious place.
 Also there were glitches with a fast disk change. I corrected and optimized the code well and added support for Attiny13a.
 That's basically it :)
 Before the firmware, pay attention to define and the function inject_SCEx (). In the comments all are indicated.
 
