{"action":"created","issue":{"url":"https://api.github.com/repos/pololu/dual-vnh5019-motor-shield/issues/7","labels_url":"https://api.github.com/repos/pololu/dual-vnh5019-motor-shield/issues/7/labels{/name}","comments_url":"https://api.github.com/repos/pololu/dual-vnh5019-motor-shield/issues/7/comments","events_url":"https://api.github.com/repos/pololu/dual-vnh5019-motor-shield/issues/7/events","html_url":"https://github.com/pololu/dual-vnh5019-motor-shield/issues/7","id":70316578,"number":7,"title":"Using servos with two dual-vnh5019-motor-shields causes one motor to fail","user":{"login":"photodude","id":10253980,"avatar_url":"https://avatars.githubusercontent.com/u/10253980?v=3","gravatar_id":"","url":"https://api.github.com/users/photodude","html_url":"https://github.com/photodude","followers_url":"https://api.github.com/users/photodude/followers","following_url":"https://api.github.com/users/photodude/following{/other_user}","gists_url":"https://api.github.com/users/photodude/gists{/gist_id}","starred_url":"https://api.github.com/users/photodude/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/photodude/subscriptions","organizations_url":"https://api.github.com/users/photodude/orgs","repos_url":"https://api.github.com/users/photodude/repos","events_url":"https://api.github.com/users/photodude/events{/privacy}","received_events_url":"https://api.github.com/users/photodude/received_events","type":"User","site_admin":false},"labels":[],"state":"closed","locked":false,"assignee":null,"milestone":null,"comments":2,"created_at":"2015-04-23T05:50:28Z","updated_at":"2015-04-25T15:28:50Z","closed_at":"2015-04-24T19:28:19Z","body":"Recently ran into an issue where Using a servo on a Mega 2560 with two dual-vnh5019-motor-shields to drive 4 motors causes one motor to fail.\r\n\r\nAll 4 motors work fine until servo.write is in the loop then one of the motors will not turn on. \r\n\r\nSeems something in the dual-vnh5019-motor-shield library and the servo.h library conflict"},"comment":{"url":"https://api.github.com/repos/pololu/dual-vnh5019-motor-shield/issues/comments/96223212","html_url":"https://github.com/pololu/dual-vnh5019-motor-shield/issues/7#issuecomment-96223212","issue_url":"https://api.github.com/repos/pololu/dual-vnh5019-motor-shield/issues/7","id":96223212,"user":{"login":"photodude","id":10253980,"avatar_url":"https://avatars.githubusercontent.com/u/10253980?v=3","gravatar_id":"","url":"https://api.github.com/users/photodude","html_url":"https://github.com/photodude","followers_url":"https://api.github.com/users/photodude/followers","following_url":"https://api.github.com/users/photodude/following{/other_user}","gists_url":"https://api.github.com/users/photodude/gists{/gist_id}","starred_url":"https://api.github.com/users/photodude/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/photodude/subscriptions","organizations_url":"https://api.github.com/users/photodude/orgs","repos_url":"https://api.github.com/users/photodude/repos","events_url":"https://api.github.com/users/photodude/events{/privacy}","received_events_url":"https://api.github.com/users/photodude/received_events","type":"User","site_admin":false},"created_at":"2015-04-25T15:28:50Z","updated_at":"2015-04-25T15:28:50Z","body":"Hi, @ryantm\r\nmy setup maybe \"pretty advanced\" but is fairly simple still. (Mega 2560 + dual-vnh5019-motor-shield + xbee shield + 1 servo) I'm using the dual-vnh5019-motor-shield library, the standard arduino  servo.h library, Arduino IDE 1.6.3, and serial3 for the xbee. We found a temporary \"work around\" for the servo issue by using the old softwareServo library and updating that library for arduino IDE 1.x\r\n \r\nI've done a quick search in the forum. According to this [tread in the forum](http://forum.pololu.com/viewtopic.php?f=15&t=7439&p=35443&hilit=servo+vnh5019#p35443) [and this thread](http://forum.pololu.com/viewtopic.php?f=15&t=5303&p=26157&hilit=servo+vnh5019#p26157) there is a known issue with timer conflicts between the dual-vnh5019-motor-shield and the servo library when used with an Uno. I believe a similar issue is occurring with the Mega 2560. \r\n\r\nBased on this information, I think the best solution would be to provide an optional parameter to switch the timer used by the dual-vnh5019-motor-shield. (changing or modifying timers is unfortunately beyond my arduino skill level at the moment) "}}