libmodbus
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stephane
modbus_write_registers return -1, reason connection timeout
use version 3.1.6 on linux, The client executes the modbus_write_registers function once a second, why once in a while modbus_write_registers(ctx[index], addr, count, buf) return -1, and modbus_strerror(errno) show connection timed out?
int addr = 259; int count = 1; uint16_t buf[10]=[1000]
The connection settings are as follows
` modbus_set_byte_timeout(ctx[index], 0, 200 * 1000);
modbus_set_indication_timeout(ctx[index], 0, 100 * 1000);
modbus_set_response_timeout(ctx[index], 0, 200 * 1000);
if (-1 == modbus_connect(ctx[index])) {
SPDLOG_ERR(channel_http, "[ModbusCreate] connect {}:{} faild reason:{}", ip, port, modbus_strerror(errno));
modbus_free(ctx[index]);
ctx[index] = NULL;
ret = "-1,{},";
return;
}
int socket = modbus_get_socket(ctx[index]);
int keepAlive = 1;
int keepIdle = 1;
int keepInterval = 1;
int keepCount = 3;
setsockopt(socket, SOL_SOCKET, SO_KEEPALIVE, (void*)&keepAlive, sizeof(keepAlive));
setsockopt(socket, SOL_TCP, TCP_KEEPIDLE, (void*)&keepIdle, sizeof(keepIdle));
setsockopt(socket, SOL_TCP, TCP_KEEPINTVL, (void*)&keepInterval, sizeof(keepInterval));
setsockopt(socket, SOL_TCP, TCP_KEEPCNT, (void*)&keepCount, sizeof(keepCount));`
if using modbus_set_byte_timeout, the modbus_set_response_timeout is not working?
Maybe I should use modbus_ set_ indication_ timeout (ctx [index], 0, 0), let the server wait all the time, so that there will be no connection timeout problem?
