siemens s5 115 u problem

Hi..
I have one problem with siemens S5 115u cpu 942B. In that cpu, EPROM module of 32kb is installed.
Now, i changed one segment in the program of that cpu. Then one dialogue opens with text " program in eprom , continue? ". I pressed " yes ". Now, when i checked program again that segment is not modified. So, i want to know why it happened.

Also, i try by changing program offline and then downloading it in cpu but when i try to transfer same message appears and when i press " yes " , it shows " 0 block tranferred ".That means my modified block doesnt transferred to cpu.

So, i want to know that why i couldnt change anything in program of cpu.it doesnt work online or offline.

Also if editing is not possible with this cpu, what changes i can do in system to make editing possible?can i use RAM module or CPU 943/944.

Also, i attached pics of errors for reference.

have you tried removing the EEPROM and selecting block list "A" then transfered?

Hi..
thanx but i tried that also..
my all blocks couldnt get downloaded bcoz my program size is larger than internal mem of cpu 942. so it shows message of " memory inedequate ".
so only some of the blocks can be downloaded.

I’m afraid that you will have to “burn” the EPROM again with the new software. If you have an EPROM (not EEPROM) you will also need an UV-light to erase it first.

I have one problem with siemens S5 115u cpu 942B. In that cpu, EPROM module of 32kb is installed.
...
can i use RAM module or CPU 943/944.

Click to expand...

It is possible to use a RAM module in the 942B CPU. The order code is 6ES5 375-0LD31(32 Kbytes). If you change the CPU for a 943/944 you won’t need a RAM module anymore because those CPU’s can store the entire program on the internal RAM. Remember that you still need a (E)EPROM or backup batteries to recover after a power failure.

You can try this (it is approximate - due to long time without practice)
Use your PG to:
- Read system memory - you will find it under one of the function keys - don't remember which.
- Find the pointer address for the module you want to change (this is "DB0" and is not accessible as a normal DB).
- Change the pointer address to 0000H
= now this address should be free for you to transfer your new block - and it will be transfered to RAM (not the EPROM).
If your 115 have a battery, I think the change will last - you must check it out.

K