[SOLVED] what is the use of FILL command on intel hex file

[vishu489]

Hello friends,

recently i have come through this s-record fill command, used to fill data gaps with some arbitrary byte. I'm not able to figure out what is the advantage of using fill command over hex file before calculating check sum?


Thanks

 

[hanif]

this is used to fill the holes where your data donot lie for further check following

http://srecord.sourceforge.net/man/man1/srec_examples.html#FILLING%20THE%20BLANKS

 

[betwixt]

It has little use but in some situations the data in a hex file has to be continuous. Normal hex files can have gaps in the address field which means some part of the device are not programmed. Using FILL is a way of ensuring the gaps have something in them. Some programming equipment gets confused when it sees jumps in the addresses and there is also a potential issue with security if parts of a reprogrammed device still holds old bytes that were not overwriten. Example: In a project I did a few years ago, the hex file was for programming a 27C512 EPROM which was used as a timing pattern generator, all the addresses were read in sequence and each of the data bits read from the memory made a complex timing pattern. It places it needed hundreds of repeated bytes so the FILL command was useful to simplify the source file, without it there would have to be hundreds of additional identical lines, each producing one byte of output.

Brian.

 

[vishu489]

Thanks a lot friends!