# Bus communication error: -84 **URL:** \ **Category:** Uncategorized\ **Created:** [February 21, 2022, 7:45am UTC](https://forum.sierrawireless.com/t/bus-communication-error-84/26319 "2022-02-21T07:45:53Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![T\_a](https://avatars.discourse-cdn.com/v4/letter/t/57b2e6/32.png) [@T\_a](https://forum.sierrawireless.com/u/T_a)\ **Post date:** [February 21, 2022, 7:45am UTC](https://forum.sierrawireless.com/t/bus-communication-error-84/26319/1 "2022-02-21T07:45:53Z")
I have install the driver and get this error how can I fix it?? [101.946231] sdhci: =========================================== [101.946282] wfx-sdio mmc0:0001:1: write32: bus communication error: -84 [101.954796] wfx-sdio mmc0:0001:1: bus returned an error during first write access. Host configuration error? [101.963722] \>\>\>\>\> err2 wfx\_init\_device(wdev) [101.963733] \>\>\>\>\> err2 wfx\_probe\<4\>[101.964001] wfx-sdio: probe of mmc0:0001:1 failed with error -5 ![Screenshot from 2022-02-21 16-41-03](https://us1.discourse-cdn.com/flex025/uploads/sierrawireless/original/2X/0/0967e2914a73485f2adab4c97a1a0a31651b441a.png) error is at line: 337 [main.c](https://forum.sierrawireless.com/uploads/short-url/b6ItYMcRnTmOYxdpq49xHsHNflB.c) (13.5 KB) ---
**Author:** ![jerdung](https://avatars.discourse-cdn.com/v4/letter/j/82dd89/32.png) [@jerdung](https://forum.sierrawireless.com/u/jerdung)\ **Post date:** [February 22, 2022, 5:14am UTC](https://forum.sierrawireless.com/t/bus-communication-error-84/26319/2 "2022-02-22T05:14:29Z")
Hi T\_a, What device and current firmware are you using? Do you follow instruction from Sierra source page? Thanks, ---
**Author:** ![T\_a](https://avatars.discourse-cdn.com/v4/letter/t/57b2e6/32.png) [@T\_a](https://forum.sierrawireless.com/u/T_a)\ **Post date:** [February 22, 2022, 6:32am UTC](https://forum.sierrawireless.com/t/bus-communication-error-84/26319/3 "2022-02-22T06:32:11Z")
I have use WP7605 Module and the pic below is fw that I have used. ![Screenshot from 2022-02-22 15-30-20](https://us1.discourse-cdn.com/flex025/uploads/sierrawireless/original/2X/b/b7c74930ac7b56b9b24c0dc498b5b0b698ff0c7a.png) ---
**Author:** ![jerdung](https://avatars.discourse-cdn.com/v4/letter/j/82dd89/32.png) [@jerdung](https://forum.sierrawireless.com/u/jerdung)\ **Post date:** [February 22, 2022, 9:24am UTC](https://forum.sierrawireless.com/t/bus-communication-error-84/26319/4 "2022-02-22T09:24:04Z")
Hi T\_a, To install driver on Linux, please download and extract the package named “MBPL\_Drivers\_R24\_ENG3-src.tar” from the link below. [https://source.sierrawireless.com/resources/airprime/software/mbpl/mbpl-software-latest/#sthash.fwEgsWHj.dpbs](https://source.sierrawireless.com/resources/airprime/software/mbpl/mbpl-software-latest/#sthash.fwEgsWHj.dpbs) Choose PCIe or USB, then follow readme.txt step-by-step to install the driver. Thanks, ---
**Author:** ![T\_a](https://avatars.discourse-cdn.com/v4/letter/t/57b2e6/32.png) [@T\_a](https://forum.sierrawireless.com/u/T_a)\ **Post date:** [February 22, 2022, 9:50am UTC](https://forum.sierrawireless.com/t/bus-communication-error-84/26319/5 "2022-02-22T09:50:09Z")
hello, jerdung Does this driver is for ubuntu? I have install to my ubuntu then my /ttyUSB0-2 is lost how can I get it back?? ---
**Author:** ![jerdung](https://avatars.discourse-cdn.com/v4/letter/j/82dd89/32.png) [@jerdung](https://forum.sierrawireless.com/u/jerdung)\ **Post date:** [February 22, 2022, 10:28am UTC](https://forum.sierrawireless.com/t/bus-communication-error-84/26319/6 "2022-02-22T10:28:54Z")
Hi T\_A Yes, this driver is for ubuntu. AT port interface should be exposed as /dev/ttyUSB0 or dev/ttyUSB2. Could you try to reconnect your module to the host? Thanks, ---
**Author:** ![T\_a](https://avatars.discourse-cdn.com/v4/letter/t/57b2e6/32.png) [@T\_a](https://forum.sierrawireless.com/u/T_a)\ **Post date:** [February 22, 2022, 10:33am UTC](https://forum.sierrawireless.com/t/bus-communication-error-84/26319/7 "2022-02-22T10:33:12Z")
I have reconnect my module and it still cannot find /dev/ttyUSB0 to /dev/ttyUSB2 Are you sure that it can use with wp7605 module? before I install the driver , I can still see USB0. ![Screenshot from 2022-02-22 19-40-40](https://us1.discourse-cdn.com/flex025/uploads/sierrawireless/original/2X/c/c8079e730055373ae561767c630dafd08dac2e78.png) ---
**Author:** ![T\_a](https://avatars.discourse-cdn.com/v4/letter/t/57b2e6/32.png) [@T\_a](https://forum.sierrawireless.com/u/T_a)\ **Post date:** [February 22, 2022, 10:56am UTC](https://forum.sierrawireless.com/t/bus-communication-error-84/26319/8 "2022-02-22T10:56:00Z")
However, how can i fix “wfx-sdio mmc0:0001:1: write32: bus communication error: -84” ?? ---
**Author:** ![jerdung](https://avatars.discourse-cdn.com/v4/letter/j/82dd89/32.png) [@jerdung](https://forum.sierrawireless.com/u/jerdung)\ **Post date:** [February 22, 2022, 11:18am UTC](https://forum.sierrawireless.com/t/bus-communication-error-84/26319/9 "2022-02-22T11:18:50Z")
Hi T\_a, MBPL is the official driver for all WP76xx products. It’s strange that your AT interface is not shown as ttyUSB0 or ttyUSB2. I’m trying to investigate that. > [@T\_a](#): > > I have install the driver and get this error how can I fix it?? > [101.946231] sdhci: =========================================== > [101.946282] wfx-sdio mmc0:0001:1: write32: bus communication error: -84 Where did you get the driver before? I’m not sure the driver that isn’t on Sierra source page could work properly. Thanks, ---
**Author:** ![T\_a](https://avatars.discourse-cdn.com/v4/letter/t/57b2e6/32.png) [@T\_a](https://forum.sierrawireless.com/u/T_a)\ **Post date:** [February 23, 2022, 12:32am UTC](https://forum.sierrawireless.com/t/bus-communication-error-84/26319/10 "2022-02-23T00:32:15Z")
I have install this ( [GitHub - SiliconLabs/wfx-linux-driver: Silicon Laboratories WFx Wi-Fi linux driver source code](https://github.com/SiliconLabs/wfx-linux-driver) ) driver to wp76xx module. I got those error in dmesg after I had insmod the driver. [wf200.zip](https://forum.sierrawireless.com/uploads/short-url/vSiIH2U4JG6xNAPIVutfQSWRslH.zip) (3.9 MB) ![Screenshot from 2022-02-16 13-39-06](https://us1.discourse-cdn.com/flex025/uploads/sierrawireless/original/2X/5/51883c152ed8aa0c60616f59b705135af05d98ca.png) ---
**Author:** ![jerdung](https://avatars.discourse-cdn.com/v4/letter/j/82dd89/32.png) [@jerdung](https://forum.sierrawireless.com/u/jerdung)\ **Post date:** [February 23, 2022, 9:50am UTC](https://forum.sierrawireless.com/t/bus-communication-error-84/26319/11 "2022-02-23T09:50:30Z")
Hi T\_a, This driver is provided by SiliconLabs so it’s is out of our scope. You should post the topic in SiliconLabs forum for support. The disappearance of ttyUSB0 may be due to a conflict between SiliconLabs driver and MBPL driver. You can use the commands below to remove MBPL driver: sudo rm /lib/modules/$(uname -r)/kernel/drivers/usb/serial/usb\_wwan.ko sudo rmmod qcserial sudo rmmod cdc\_mbim Then reboot Linux. Thanks,