freeport for Siemens s7-200

When you are using freeport communication mode on Siemens S7-200 , once you got enabled the freeport mode changing the configuration, How can we go back to the PPI protocol in order for us to have communication with the PLC again?

I don't know if you have the manual for the S7-200, but in appendix D (regarding Special Memory Bits) it is described how to use the position of the mode switch todo this. I have once used this and in my program there was a subroutine to do this. This is the listing of this routine:

NETWORK 39
SBR 0

NETWORK 40
//Stop/Run/Term switch in term position:
//-reset comms, put port in PPI mode, detach and disable
//interrupts
//
LDN SM0.7
O SM0.1
MOVB 16#C8, SMB30
DTCH 8
MOVB 0, VB516
DISI

NETWORK 41
//Switch in Run position:
//-initialize freeport mode, enable interrupts. Needs to be
//one-shotted so that ISR0 can detatch itself when complete,
//and attach ISR1
//
LD SM0.7
EU
LD SM0.7
A SM0.1
OLD
MOVB 16#49, SMB30
ATCH 0, 8
ENI

NETWORK 42
//51h=2400 baud
//4Dh=4800 baud
//49h=9600 baud
//45h=19200 baud
RET

Kind regards,

The "Free Port Mode" is part of the program running and accessing one of the ports. You can use the second port for PPI or put the mode switch in the STOP postion and then back to the TERM position to control from the software.

This will disable freeport and turn it back to PPI when the switch is in 'TERM'

  SM0.7           SM30.0

---] [--------------()---

This is for port 0. If on port 1 use SM130.0 (I think)

Paraffin power,

that's OK if and only if you're using the same baudrate and the same bitframing on both freeport and MPI. If that's not the case, see my previous post, which deals with all settings.

Kind regards,

Thanks & another questio

jvdcande said:

Paraffin power,

that's OK if and only if you're using the same baudrate and the same bitframing on both freeport and MPI. If that's not the case, see my previous post, which deals with all settings.

Kind regards,

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