Michael Rigby-Jones wrote:
> /* Jump table entry macro - target dependant */
> #define TB_ENTRY_FAR(addr) __asm__ __volatile__ ("jmp " addr : : )
>=20
> void JumpTable (void)
> {
>    // FAR format (each entry 2 words)
>    TB_ENTRY_FAR("MyFunc1");  // quotes are necessary
>    TB_ENTRY_FAR("MyFunc2");
>    TB_ENTRY_FAR("MyFunc3");
>    TB_ENTRY_FAR("MyFunc4");
>    TB_ENTRY_FAR("MyFunc5");
> }

OK, in this case, MyFunc1, etc. are the addresses of the actual functions,
used as arguments to the jmp instructions.

> And then I define the pointers to the actual function. JT_BASE is defined=
 by
> the makefile, so I only have to change this in one place if I ever needed=
 to
> move it.
>=20
> #define MyFunc1 (a) 	((fp_u8_pu8)(JT_BASE+0))(a)
> #define MyFunc2 ()	((fp_s16_v)(JT_BASE+2))()
> #define MyFunc3 (a)	((fp_b_u8)(JT_BASE+4))(a)
> #define MyFunc4 (a)	((fp_v_b)(JT_BASE+6))(a)
> #define MyFunc5 ()	((fp_pu8_v)(JT_BASE+8))()

This doesn't look right. These are pointers into the jump table, not pointe=
rs
to the actual functions. These are meant to be used in the application code=
,
aren't they? As such, shouldn't they should use a different set of names,
rather than MyFunc1, etc. (e.g., JTFunc1, etc.)?

-- Dave Tweed
--=20
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