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FIELD UPDATES FOR FLASH BASED ST7 APPLICATIONS USING A PC COMM PORT

the destination is within sector0 and so the two will always stay “in sync”. At power-up reset we

always want to execute code in sector0 which is write protected and gives the decision point

to either read in an S-Records file to update sector1 or exit to execute normal code in sector1.

The exit to sector1 is done via a jump to absolute address $FDFC which is an entry in the skip-

jump table containing a re-directing jump to “start”.

Note:

Time delays within this program are implemented as simple countings loops. If the

main crystal clock is other than 8 Mhz then times will change accordingly.