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View Full Version : Boot-loaders and run mode


BaileyAmps
02-23-02, 08:52 AM
I've got an NMI-0012 board with the Motorola boot loader. The boot loader copies the program to RAM, but what makes the board run the program?

nmitech
02-25-02, 01:50 PM
Startup Code
At power up or reset, CPU control is transferred to the routine beginning at the Bootloader code. This
routine checks the state of PORTDLC bit number 0. If PORTDLC bit number 0 is equal to a logic ‘0’, the
Bootloader code are copied from Flash into the on-chip RAM and CPU control is passed to the bootloader code in RAM. If PORTDLC bit number 0 is equal to a logic
‘1’, CPU control is transferred to the program defined by the address in the secondary reset vector, $F7FE-$F7FF.

Secondary Interrupt Vector Addresses
Reserved -------------- $F7C0 – $F7CF
BDLC (J1850) --------- $F7D0
ATD --------------------- $F7D2
Reserved -------------- $F7D4
SCI 0 ------------------- $F7D6
SPI ---------------------- $F7D8
Pulse Acc. Input Edge $F7DA
Pulse Acc. Overflow - $F7DC
Timer Overflow ------ $F7DE
Timer Channel 7 ---- $F7E0
Timer Channel 6 ---- $F7E2
Timer Channel 5 ---- $F7E4
Timer Channel 4 ---- $F7E6
Timer Channel 3 ---- $F7E8
Timer Channel 2 ---- $F7EA
Timer Channel 1 ---- $F7EC
Timer Channel 0 ---- $F7EE
Real Time Interrupt - $F7F0
IRQ -------------------- $F7F2
XIRQ ------------------- $F7F4
SWI -------------------- $F7F6
Illegal Opcode Trap - $F7F8
COP Failure Reset --- $F7FA
Clock Mon. Fail Reset $F7FC
Reset ------------------- $F7FE