Instructions:
When you attempt to download programs in various CPUs of the first generation (S7-21x), you get the following system message: "The CPU does not support this function".
This message occurs when using the S7-200 RS-232/ PPI Multi Master cable (6ES7 901-3CB30-0XA0) or the S7-200 USB/ PPI Multi Master cable (6ES7 901-3DB30-0XA0) together with older versions of S7-21x CPU.

The USB and PC/ PPI Multi Master cable cannot be used with all S7-200 CPUs of the first generation. These communication cables only work with CPUs 212 and 214, release 1.10 or higher, and all CPUs 215 and 216.
CPUs of the 212 and 214 series of releases less than 1.10 do not support the communications protocol required for downloading into the CPU.

The RS-232/ PPI Multi Master cable (with 8 DIP switches) also works with CPUs of the first generation if DIP switch number 5 is set to PPI/freeport ("0"). To accept the change the cable has to be de-energized by switching the S7-CPU 200 off and then on again, or by removing the cable from the S7-CPU 200 and then plugging it in again.

Note:
The following cables are multimaster-compatible:   
 

Product	Order number
Intelligent RS232/PPI cable with built-in RS232/RS485 converter	6ES7 901-3CB30-0XA0
Intelligent USB/PPI cable with built-in USB/RS485 converter	6ES7 901-3DB30-0XA0