ICP DAS USA I-7521 User Manual page 40

The data received by COM2 is "ABCD" where CrLfmode=0 (the <CR>
character is removed) and "ABCD" is sent to COM1 where CrLfmode=4
(nothing adding). So the device receives the string "ABCD", not "ABCD<CR>",
and doesn't give any response.
Command transformation:
":01ABCD<CR>",PC-->"ABCD",com2-->"ABCD",com1-->"ABCD", device
Situation 2:
I-7522A, COM2 CrLfmode=0, COM1 CrLfmode=0
The data received by COM2 is "ABCD" where CrLfmode=0 (the <CR>
character is removed) and "ABCD<CR>" is sent to COM1 where CrLfmode=0
(the <CR> character is removed). So the device receives the string
"ABCD<CR>", and gives the response "EFGH<CR>".
The data received by COM1 is "EFGH" where CrLfmode=0 (the <CR>
character is removed and "EFGH<CR>" is sent to COM2 where CrLfmode=0
(the <CR> character is added). So the PC receives the string "EFGH<CR>".
Command transformation:
":01ABCD<CR>",PC -->"ABCD",com2 -->"ABCD<CR>",com1 -->
"ABCD<CR>", device
Response transformation:
"EFGH<CR>",device -->"EFGH",com1 -->"EFGH<CR>",com2 -->
"EFGH<CR>",PC
Situation 3:
I-7522A, COM2 CrLfmode=4, COM1 CrLfmode=4
The data received for COM2 is "ABCD<CR>" where CrLfmode=4 (nothing
added) and "ABCD<CR>" is sent to COM1 where CrLfmode=4 (nothing
added). So the device receives the string "ABCD<CR>", and gives
the response "EFGH<CR>".
The data received for COM1 is "EFGH<CR>" where CrLfmode=4 (nothing
added) and "EFGH<CR>" is sent for COM2 where CrLfmode=4 (nothing
added). So the PC receives the string "EFGH<CR>".
Command transformation:
":01ABCD<CR>",PC -->"ABCD<CR>",com2 -->"ABCD<CR>",com1 -->
"ABCD<CR>", device
Response transformation:
"EFGH<CR>",device --> "EFGH<CR>",com1 -->"EFGH<CR>",com2
--> "EFGH<CR>",PC
I-7521/I-7522/I-7522A/I-7523/I-7524/I-7527 User's Manual,Ver2.5 Aug.2015
40