Yaskawa V7 PROFIBUS-DP - Manual (Page 41)

Network Communications 3-13
Handshaking
The handshaking register is necessary to synchronize the send/receive timing of parameter access message data between the PROFIBUS-
DP Master and the V7 PROFIBUS-DP Option. One register (byte 32 of the 16 word input/output message or byte 12 of the 6 word
input/output message) in the input and output parameter access message areas is dedicated to handshaking. The data set in the output area
of the master becomes enabled in the V7 PROFIBUS-DP Option when the status of the HS bit, bit 7, is changed.
‹ Command Handshaking Register PROFIBUS-DP Master To V7
Table 3.16 – Handshaking Output Register Bit Definitions
Bit Name Function
7 HS
Handshaking bit. Used to synchronize the data exchange. Toggled when a new command is transmitted. This bit must be
cleared after power-up or re-initialization by the Master program.
6 - 0 Not used.
‹ Response Handshake Register V7 To PROFIBUS-DP Master
Table 3.17 – Handshaking Input Register Bit Definitions
Bit Name Function
7 HS Handshaking bit. Used to synchronize the data exchange. Toggled when a new response is transmitted
6 - 5 STATUS
Status of data exchanged between Communication Option and drive.
00H: Idle
01H: Sending parameter access message to drive
10H: Waiting for parameter access response from drive
11H: Response received from drive
4 - 1 WD Watch Dog Counter, incremented approximately every 64 ms.
0 Not used