---
title: "Serial ports do not work"
url: "https://maker.wiznet.io/forum/9879"
markdown_url: "https://maker.wiznet.io/forum/9879/md"
type: "Forum topic"
category: "Wireless"
author: "limit"
created: "2014-01-31T11:20:01+09:00"
last_activity: "2017-05-04T08:31:18+09:00"
language: "en"
views: 454
replies: 1
source: "WIZnet Makers forum (https://maker.wiznet.io/forum/)"
---

# Serial ports do not work

## Question

Asked by limit on 2014-01-31 in Wireless.

Hi!

I use my custom board with WizFi630. I can successfully use all ethernet and wireless interfaces (currently it looks like one small switch:)) in any operation mode. However, I can not communicate with WizFi630 by means of serial interfaces. I tried to use three apps for sending commands(<+++>, , , etc. in any combinations) through my COM-port to serial interface #1 (and also #2): Wizard Version 1.0, Device Terminal Ver. 1.0 and WIZSmartScript - no success. I see sent data on TX using oscilloscope, but no data on RX. I have connected only RxD, TxD and GND and haven’t touched RTS_N, CTS_N, RIN, etc. GPIO19 is pulled up to logical “1” while “Serial Command Mode - Disabled”.
Maybe I should use some addtitional pins? Will it work on such minimal RS232 configuration as I have?

Thanks!

## Replies

### Reply 1 by ssekim, 2014-02-11

Hi Limit

1. Check GPIO
   Serial Setting → Serial Port #1 → Data Packing Condition → Command mode
   Check Enable(Enable:HW GPIO Used) and change the switch of WizFi630-EVB.

2. Do .
   Please try it again, after factory default.

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Source: https://maker.wiznet.io/forum/9879