1、【修复】FreeModbus V1.5从机源码中遗留的读保持寄存器一处书写错误。

Signed-off-by: armink <[email protected]>

Author: armink

FreeModbus/modbus/functions/mbfuncholding.c

@@ -183,7 +183,7 @@ eMBFuncReadHoldingRegister( UCHAR * pucFrame, USHORT * usLen )
         usRegAddress++;
 
         usRegCount = ( USHORT )( pucFrame[MB_PDU_FUNC_READ_REGCNT_OFF] << 8 );
-        usRegCount = ( USHORT )( pucFrame[MB_PDU_FUNC_READ_REGCNT_OFF + 1] );
+        usRegCount |= ( USHORT )( pucFrame[MB_PDU_FUNC_READ_REGCNT_OFF + 1] );
 
         /* Check if the number of registers to read is valid. If not
          * return Modbus illegal data value exception.