---
title: "W7500P Slow I/O"
url: "https://maker.wiznet.io/forum/12119"
markdown_url: "https://maker.wiznet.io/forum/12119/md"
type: "Forum topic"
category: "MCU & Boards"
author: "joaopaulob"
created: "2017-01-30T14:50:19+09:00"
last_activity: "2017-05-30T20:22:42+09:00"
language: "en"
views: 847
replies: 1
source: "WIZnet Makers forum (https://maker.wiznet.io/forum/)"
---

# W7500P Slow I/O

## Question

Asked by joaopaulob on 2017-01-30 in MCU & Boards.

Hi,

I’m doing some tests with I/O speed on W7500P and I am achieving only 2MHz on the following code:

[code]
DigitalOut myled(PC_8);

int main() {

*(volatile uint32_t *)(0x41001014) = 0x0060100; // set to 48 MHz

```
while(1) {
    *(volatile uint32_t *)0x44000000 |= 0x100; // IO high
    *(volatile uint32_t *)0x44000000 &= 0xEFF; // IO low
}
```

} [/code]

If the core clock is 48 MHz, how much is the FSB? Is there any way to speed up the I/O transition? I’m implementing a 16bit display and need faster I/O.

Environment: mbed and WIZwiki-W7500P

Best regards,

## Replies

### Reply 1 by lawrence, 2017-04-11

hello, joaopaulob

thank you for your interest in w7500p

I am not sure you test with st micro or other mcu.

even st micro mcu has no support over 2MHz gpio speed.

I do not no what you want to do with gpio but I think any mcu could not suppert it.

thank you

lawrence

---

Source: https://maker.wiznet.io/forum/12119