New feature coming: Thunderclock Pro support

[BLuRry <brendan.robert@gmail.com>]

I have successfully implemented Thunderclock Pro support for Jace.  The sourceforge build doesn't have this yet, but I have checked in the source code for the impatient armed with java compilers.

Just clock support wasn't sufficient (I'm really picky), I have also written a patcher for that darn Prodos year issue that everyone always complains about:

    private void performProdosPatch() {
        PagedMemory ram = Computer.getComputer().getMemory().activeRead;
        if (patchLoc > 0) {
            // We've already patched, just validate
            if (ram.readByte(patchLoc) == (byte) MOS65C02.OPCODE.LDA_IMM.getCode()) {
                return;
            }
        }
        int match = 0;
        int matchStart = 0;
        for (int addr = 0x08000; addr < 0x010000; addr++) {
            if (ram.readByte(addr) == DRIVER_PATTERN[match]) {
                match++;
                if (match == DRIVER_PATTERN.length) break;
            } else {
                match = 0;
                matchStart = addr;
            }            
        }
        if (match != DRIVER_PATTERN.length) {
            return;
        }
        patchLoc = matchStart + DRIVER_OFFSET;
        ram.writeByte(patchLoc, (byte) MOS65C02.OPCODE.LDA_IMM.getCode());
        int year = Calendar.getInstance().get(Calendar.YEAR) % 100;
        ram.writeByte(patchLoc+1, (byte) year);
        ram.writeByte(patchLoc+2, (byte) MOS65C02.OPCODE.NOP.getCode());
        ram.writeByte(patchLoc+3, (byte) MOS65C02.OPCODE.NOP.getCode());
    }

This patch scans the active memory of the emulator for a very obvious signature of data found in the prodos clock driver which has never changed.  The driver itself moves around in the prodos kernel, so scanning for a signature seemed the most prudent way to find it.  Once I find the driver code, I patch the part that loads the year from a lookup table with:
  LDA #year%100
  NOP
  NOP

This will work until the end of time.  Or at least for the next 9 days.  At least the Apple calendar won't run out of time anymore (silly Mayans.)  

-B