[PLC4X-47] S7 driver silently ignores surplus ReadRequestItems

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.1.0
• Component/s: Driver-S7
• Assignee: Christofer Dutz
• Reporter: Andreas Uschold
• Created: 11/Sep/18 13:37
• Updated: 19/Sep/18 15:48
• Resolved: 14/Sep/18 10:13

Description

If a ReadRequests contains more than 19 ReadRequestItems, the driver includes only the first 19 items into a telegram sent to the PLC and silently ignores all following items.

When writing more than one Item to a PLC, the S7 driver simulates multiple writes by sending individual writes. I think in case of a similar approch should be considered.

Snippet i used to create the request:

List<ReadRequestItem<?>> reqs = new ArrayList<>();
for (int i = 1; i <= 30; i++) {
    // just the first byte of each db
    Address db = plcConnection.parseAddress("DATA_BLOCKS/" + i + "/0");
    ReadRequestItem<Byte> item = new ReadRequestItem<>(Byte.class, db);
    reqs.add(item);
}

plcReader.read(new PlcReadRequest(reqs));