42 lines
1 KiB
C
42 lines
1 KiB
C
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/**
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* Implementation of 68000 specific BIOS routines.
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*
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* NOTE: these routines are not called directly but are instead called through TRAP#13
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*/
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#define TEXT_MATRIX_0 ((volatile char *)0x00AFA000)
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typedef void (* interrupt_handler)();
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static int text_cursor_0 = 0;
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int impl_bconout(long context, char c) {
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TEXT_MATRIX_0[text_cursor_0++] = c;
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return 0;
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}
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/*
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* Set an exception handler
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*
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* If handler is the nil pointer, just return the current value.
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*
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* Inputs:
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* number = the number of the 68000 exception vector (2 - 255)
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* handler = pointer to the handler (must be coded as an interrupt handler)
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*
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* Return:
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* the previous value
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*/
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long impl_setexc(long context, unsigned short number, void (* handler)()) {
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interrupt_handler * address = 0;
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long result = 0;
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if ((number > 1) && (number < 256)) {
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address = (interrupt_handler *)(number * 2);
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result = (long)(*address);
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if (handler != 0) {
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*address = handler;
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}
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}
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return result;
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}
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