---
title: "WIZ750SR enter to command mode"
url: "https://maker.wiznet.io/forum/15270"
markdown_url: "https://maker.wiznet.io/forum/15270/md"
type: "Forum topic"
category: "Serial-to-Ethernet & ConfigTool"
author: "uncleg"
created: "2024-08-29T12:47:13+09:00"
last_activity: "2024-11-07T21:07:39+09:00"
language: "en"
views: 15
replies: 3
source: "WIZnet Makers forum (https://maker.wiznet.io/forum/)"
---

# WIZ750SR enter to command mode

## Question

Asked by uncleg on 2024-08-29 in Serial-to-Ethernet & ConfigTool.

Hello,
I have a question about WIZ750SR TTL version.
We have noticed that when there is not connected ethernet cable then entering to command mode by HW_TRIG takes about 10 seconds.
When ethernet cable is connected then it works as expected - entering to command mode by HW_TRIG takes aprox. 1 second.
Is it some kind of bug or by design?
Thank You and best regards,

## Replies

### Reply 1 by Alan, 2024-08-30

When I run it on my device, it works well regardless of the Ethernet cable. I think the environmental impact has had on the board.

### Reply 2 by uncleg, 2024-09-09

Thank You for a feedback.
We have made some more tests directly on the WIZ module (WIZ750SR ver1.2) and the problem still occurs.
Maybe we are doing something wrong?
We have connected only VCC pins, GND pins and short between HW_TRIG and GND pins - we want to enter to command mode.
If there is ethernet cable connected then we need to wait about 8 seconds after power up (blue LED).
If there is not ethernet cable connected then we can’t get in to command mode.
Do we have to make some special preparation for using HW_TRIG pin?

Best regards,

### Reply 3 by uncleg, 2024-11-07

Hello,

I would like to refresh the topic.

I've bought EVB kit for WIZ750SR and made some more test.

It looks that the problem occurs only when where is set DHCP mode (command IM1).

I think that after reboot, when DHCP mode is active and there is no ethernet cable, WIZ750SR tries to obtain IP address from DHCP server and wait 30 seconds (timeout).

Only command which works is enter command mode code (default +++, which is disabled) - all others are ignored.

Can You confirm that?

Is it possible to walkaround that problem?

Thank You and best regards,

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Source: https://maker.wiznet.io/forum/15270