Freescale Semiconductor M5407C3, User Manual, Page: 66 / 118

2-40 M5407C3 User’s Manual
TRAP #15 Functions
Assembly example:
move.l #$0010,d0 Select the function
trap #15 Make the call, the input character is in d1.
C example:
int board_in_char (void)
{
asm (“ move.l#0x0010,d0”); /* select the function */
asm (“ trap#15”); /* make the call */
asm (“ move.ld1,d0”); /* put the character in d0 */
}
2.5.3 CHAR_PRESENT
This function (function code 0x0014) checks if an input character is present to receive. A
value of zero is returned in D0 when no character is present. A non-zero value in D0 means
a character is present.
Assembly example:
move.l #$0014,d0 Select the function
trap #15 Make the call, d0 contains the response (yes/no).
C example:
int board_char_present (void)
{
asm (“ move.l#0x0014,d0”); /* select the function */
asm (“ trap#15”); /* make the call */
}
2.5.4 EXIT_TO_dBUG
This function (function code 0x0000) transfers the control back to the dBUG, by
terminating the user code. The register context are preserved.
Assembly example:
move.l #$0000,d0 Select the function
trap #15 Make the call, exit to dBUG.
C example:
void board_exit_to_dbug (void)
{
asm (“ move.l#0x0000,d0”); /* select the function */
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