# GPIO is not enough on WP7607 **URL:** \ **Category:** mangOH Yellow\ **Created:** [March 31, 2021, 8:26am UTC](https://mangoh.discourse.group/t/gpio-is-not-enough-on-wp7607/7395 "2021-03-31T08:26:17Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![bruceke](https://avatars.discourse-cdn.com/v4/letter/b/0ea827/32.png) [@bruceke](https://mangoh.discourse.group/u/bruceke)\ **Post date:** [March 31, 2021, 8:26am UTC](https://mangoh.discourse.group/t/gpio-is-not-enough-on-wp7607/7395/1 "2021-03-31T08:26:17Z")
Because GPIO is not enough on WP7607 , can I use pcm , uart1 or wake\_on\_wwan pin as GPIO(is it support multi function? ) ? ---
**Author:** ![jyijyi](https://sea2.discourse-cdn.com/flex016/user_avatar/mangoh.discourse.group/jyijyi/32/997_2.png) [@jyijyi](https://mangoh.discourse.group/u/jyijyi)\ **Post date:** [March 31, 2021, 8:37am UTC](https://mangoh.discourse.group/t/gpio-is-not-enough-on-wp7607/7395/2 "2021-03-31T08:37:48Z")
You can use ioctl to control 8 wire uart You can also modify the yocto source to make those uart pin to be gpio > **[Controlling DCD, DTR, DSR lines by legato application](https://forum.legato.io/t/controlling-dcd-dtr-dsr-lines-by-legato-application/3944/15)** > > i remember those numbers are correct for DCD,DTR and DSR. ---
**Author:** ![bruceke](https://avatars.discourse-cdn.com/v4/letter/b/0ea827/32.png) [@bruceke](https://mangoh.discourse.group/u/bruceke)\ **Post date:** [April 12, 2021, 11:49am UTC](https://mangoh.discourse.group/t/gpio-is-not-enough-on-wp7607/7395/3 "2021-04-12T11:49:17Z")
Hi jyijyi, I tried to use ioctl() call to control uart1 RTS pin (and check pin status on CN601.15) , but did not see the status change ```auto #include //ioctl() call defenitions #include main() { int fd; fd = open("/dev/ttyHS0",O_RDWR | O_NOCTTY );//Open Serial Port int RTS_flag; RTS_flag = TIOCM_RTS; while(1){ printf("RTS High\n"); ioctl(fd,TIOCMBIS,&RTS_flag);//Set RTS pin sleep 2 //getchar(); printf("RTS Low\n"); ioctl(fd,TIOCMBIC,&RTS_flag);//Clear RTS pin } close(fd); } ``` So I use sysfs way to do it DCD control (should it be GPIO24?) , But it seems that there is no state change ```auto echo 24 > /sys/class/gpio/export echo out > /sys/class/gpio/gpio24/direction echo 1 > /sys/class/gpio/gpio24/value ``` Do I want to modify the kernel or is there any error in setting? (on mangOH yellow) ---
**Author:** ![jyijyi](https://sea2.discourse-cdn.com/flex016/user_avatar/mangoh.discourse.group/jyijyi/32/997_2.png) [@jyijyi](https://mangoh.discourse.group/u/jyijyi)\ **Post date:** [April 12, 2021, 12:44pm UTC](https://mangoh.discourse.group/t/gpio-is-not-enough-on-wp7607/7395/4 "2021-04-12T12:44:40Z")
You can see here on how to control the cts pin > **[UART flow control with WP7608](https://forum.legato.io/t/uart-flow-control-with-wp7608/4597/32)** > > To set RI pin as input pin: you need to first send an AT command: AT!RIOWNER=1 after that you can control the RI in linux console: echo RI \> /sys/class/gpio/export echo in \> /sys/class/gpio/gpioRI/direction cat... Also you need to recompile yocto image to control dcd dtr dsr as gpio ---
**Author:** ![bruceke](https://avatars.discourse-cdn.com/v4/letter/b/0ea827/32.png) [@bruceke](https://mangoh.discourse.group/u/bruceke)\ **Post date:** [April 15, 2021, 9:12am UTC](https://mangoh.discourse.group/t/gpio-is-not-enough-on-wp7607/7395/5 "2021-04-15T09:12:12Z")
Hi jyijyi, Thank you for kind explanation, but I use ioctl to execute on mangoh yellow and still cannot make RTS, DCD, DTR, CTS… and other pin output status change ```auto int fd; fd = open("/dev/ttyHS0",O_RDWR | O_NOCTTY );//Open Serial Port int RTS_flag = TIOCM_RTS; int DCD_flag = TIOCM_CD; int DTR_flag = TIOCM_DTR; int CTS_flag = TIOCM_CTS; while(1){ printf("RTS High\n"); ioctl(fd,TIOCMBIS,&RTS_flag);//Set RTS pin sleep(1); ioctl(fd,TIOCMBIC,&RTS_flag); ioctl(fd, TIOCMSET, &DCD_flag); sleep(1); ioctl(fd,TIOCMBIC,&DCD_flag); ioctl(fd, TIOCMSET, &DTR_flag); sleep(1); ioctl(fd,TIOCMBIC,&DTR_flag); ioctl(fd, TIOCMSET, &CTS_flag); sleep(1); ioctl(fd,TIOCMBIC,&CTS_flag); ``` (The FW version on my platform) ![image](https://us1.discourse-cdn.com/flex016/uploads/mangoh/original/2X/0/007be9c243067342082120ff20af00e4cca83043.png) So I tried to modify gpiolib-sysfs so that flow-control can be changed by sysfs , and I found that there is no “ext\_gpio\_map ext\_gpio\_wp” in my gpiolib-sysfs.c , the yocto sourcecode I used is “Legato-Dist-Source-mdm9x28-SWI9X07Y\_02.37.07.00.tar.bz2” (R16 firmware). Where can I download the appropriate FW version for compilation? ---
**Author:** ![jyijyi](https://sea2.discourse-cdn.com/flex016/user_avatar/mangoh.discourse.group/jyijyi/32/997_2.png) [@jyijyi](https://mangoh.discourse.group/u/jyijyi)\ **Post date:** [April 15, 2021, 9:27am UTC](https://mangoh.discourse.group/t/gpio-is-not-enough-on-wp7607/7395/6 "2021-04-15T09:27:08Z")
Is that you must use R16? I remember i used R13 at that time. Your code is not changing the pin status This is the code to change CTS pin ``` int arg; if (ioctl(fd1, TIOCMGET, &arg) == -1) { LE_DEBUG("ERROR: %s", strerror(errno)); } if (level) arg |= TIOCM_RTS; else arg &= ~TIOCM_RTS; if (ioctl(fd1, TIOCMSET, &arg) == -1) { LE_DEBUG("ERROR: %s", strerror(errno)); } ``` ---
**Author:** ![bruceke](https://avatars.discourse-cdn.com/v4/letter/b/0ea827/32.png) [@bruceke](https://mangoh.discourse.group/u/bruceke)\ **Post date:** [April 19, 2021, 9:19am UTC](https://mangoh.discourse.group/t/gpio-is-not-enough-on-wp7607/7395/7 "2021-04-19T09:19:30Z")
Hi jyijyi, Thanks for your quick reply I tried to rebuild the source code of Yocto and change gpiolib-sysfs.c After generating the .cwe file, combine cwe into custom-firmware image and -reflash ![image](https://us1.discourse-cdn.com/flex016/uploads/mangoh/original/2X/b/b9620a0f7fb6a13f5327646e03fb144eafc1dfd1.png) Some error occurred when we type `echo 17> /sys/class/gpio/export` ![image](https://us1.discourse-cdn.com/flex016/uploads/mangoh/original/2X/c/ce307a62f483292371193188d40fb4bf6f3d3515.png) I checked the kernel build date and found that the build date has not been updated ![image](https://us1.discourse-cdn.com/flex016/uploads/mangoh/original/2X/6/617fa8fbe3b38bf0baf1b525d8c8ff12d7de4a7c.png) Is my burning method wrong? (Or choose the wrong file) ---
**Author:** ![jyijyi](https://sea2.discourse-cdn.com/flex016/user_avatar/mangoh.discourse.group/jyijyi/32/997_2.png) [@jyijyi](https://mangoh.discourse.group/u/jyijyi)\ **Post date:** [April 19, 2021, 9:23am UTC](https://mangoh.discourse.group/t/gpio-is-not-enough-on-wp7607/7395/8 "2021-04-19T09:23:41Z")
You can directly update the yocto\_wp76xx.cwe ---
**Author:** ![bruceke](https://avatars.discourse-cdn.com/v4/letter/b/0ea827/32.png) [@bruceke](https://mangoh.discourse.group/u/bruceke)\ **Post date:** [April 19, 2021, 9:53am UTC](https://mangoh.discourse.group/t/gpio-is-not-enough-on-wp7607/7395/9 "2021-04-19T09:53:40Z")
Thanks your comment I’d re-flash mangoh with yocto\_wp76xx.4k.cwe only, but the test result is still the same, the build date and gpio sysfs have not been updated ![image](https://us1.discourse-cdn.com/flex016/uploads/mangoh/original/2X/e/e1f3d77dae48017c3a4714b66dc024437554a727.png) test result: ![image](https://us1.discourse-cdn.com/flex016/uploads/mangoh/original/2X/3/3b494d624be1263c086650275b95cba697ec4767.png) ---
**Author:** ![jyijyi](https://sea2.discourse-cdn.com/flex016/user_avatar/mangoh.discourse.group/jyijyi/32/997_2.png) [@jyijyi](https://mangoh.discourse.group/u/jyijyi)\ **Post date:** [April 19, 2021, 10:58am UTC](https://mangoh.discourse.group/t/gpio-is-not-enough-on-wp7607/7395/10 "2021-04-19T10:58:07Z")
didn’t Apr19 22:05:25 already updated? How do you change for gpiolib-sysfs.c ? You can use my yocto image for WP76 on R13: root@swi-mdm9x28-wp:~# echo 101 \> /sys/class/gpio/export root@swi-mdm9x28-wp:~# echo 102 \> /sys/class/gpio/export root@swi-mdm9x28-wp:~# microcom /dev/ttyAT ati8 Legato Ver: 20.04.0\_96205776d64ef766ba918ebe5586c885\_modified Yocto Ver: SWI9X07Y\_02.28.03.05 2020-03-09\_02:35:57 OS Ver: Linux version 3.18.131 (oe-user@oe-host) (gcc version 7.3.0 (GCC) ) #1 PREEMPT Wed Feb 26 04:17:04 UTC 2020 LK Ver: SWI9X07Y\_02.28.03.05 RootFS Ver: SWI9X07Y\_02.28.03.05 2020-03-09\_02:35:57 UserFS Ver: unknown MCU Ver: 002.011 OK > **[yocto\_wp76xx.4k\_R13\_DTR\_DSR\_DCD.cwe](https://drive.google.com/file/d/1zqsTJwtxJcBrgv6yccdE8-vzSB_YUN4G/view?usp=sharing)** > > Google Drive file. ---
**Author:** ![bruceke](https://avatars.discourse-cdn.com/v4/letter/b/0ea827/32.png) [@bruceke](https://mangoh.discourse.group/u/bruceke)\ **Post date:** [April 20, 2021, 9:30am UTC](https://mangoh.discourse.group/t/gpio-is-not-enough-on-wp7607/7395/11 "2021-04-20T09:30:18Z")
Thanks It looks like an incorrect flash command caused no update ![image](https://us1.discourse-cdn.com/flex016/uploads/mangoh/original/2X/6/679159d2107164faad974b8659d0761966aa0f80.png)