Checksum in text ASCII IBM HEX

[danielm]

Hi,
I have a problem with calculate checksum in files of injection plastic machine
When change dates in machine, It change one line and file correct, when i change valor in PC the machine says file not correct
Someone help me.
I need know calculate checksum for change lines in PC.
I send files corrects, only change data, change line $ FORMAT:

Regards

Example file one:
2015-09-14
16:37:00
98010223
14588
GL400PET P100/120 E100
LBS/SOFT
$ FORMAT:1.6037291

Example file two:
2015-09-14
16:38:02
98010223
14588
GL400PET P100/120 E100
LBS/SOFT
$ FORMAT:1.6027239

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