Gram ZFOC Serie Manual De Utilización página 53

• PC sends command package after receiving scale response 0x02.
• After PC receiving scale response 0x02 & command response
package, if needs to send command, switch to c.
• PC sends end package.
• PC terminates after receiving scale response 0x02.
Start package, fixed 6 bytes: 11 00 00 00 00 EF5
End package, fixed 6 bytes: 33 00 00 00 00 CD
Command package command response package, format is as follows:
Cmd type adr1 adr0 datlen [dat] checksum
cmd: Only 55 read command or 77 write command.
Type: Operating data type is as follows:
f9: Unit price or PLU
f4: Total price
adr1,adr0: Form 2 bytes integer adr=adr1*100+adr0
When adr is 0, stands for operating current unit price or total price
When adr is not 0, stands for operating memory area PLU, at this time adr
is PLU's positon.
adr1 = (DC+pluN*4)/100
adr0 = (DC+pluN*4)%100
datlen: Data length of reading or writing. Data length of PLU is 4
[dat]:
The data of writing command,length is decided by datlen
checksum:
(cmd+type+dar1+dar0+datalen+[dat])%100
checksum, checksum = 100-
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