SparkFun Electronics Commentsurn:uuid:214d0e4e-f1b1-d287-ce26-ac5b4c9f82492024-03-28T16:29:01-06:00SparkFun ElectronicsCustomer #1629023 on DEV-15316 - SparkFun Servo pHAT for Raspberry PiCustomer #1629023urn:uuid:d65e93a7-8473-efb0-986d-413e86a385e02021-10-11T16:48:18-06:00<p>Hello Sirs, can I use this header, and use the ribbon connection to your GPIO breadboard T connector? At the same time?</p>
Customer #1653103 on DEV-15316 - SparkFun Servo pHAT for Raspberry PiCustomer #1653103urn:uuid:8609e046-2745-b6eb-421a-ba68a5b471382021-02-04T11:15:41-07:00<p>I need to get 18 servos running (hexapod). Is it possible to run two of these on a single Raspberry Pi 4?
Thanks!</p>
QCPete on DEV-15316 - SparkFun Servo pHAT for Raspberry PiQCPeteurn:uuid:77849514-2cf7-3b62-d170-c54d002a85932020-05-01T10:30:47-06:00<p>Hi Gumercules,
Yes, you are correct. If you solder directly to the "SERVO" net (aka any one of the 5V header pins on the servo connections, aka the "middle pin"), then you can supply a higher voltage). If you don't need all 16 channels, then you could use one of them as the "input". But you could also solder to the bottom of the header. Note, there are some ideal diode circuits to keep this isolated from the rest of the board. This means that if you go this route, then you do not need to cut the PI ISO jumper.<p>You could also inject up to 6V on the RVR "5+" pin, but keep in mind that this will also power the PCA9865 with your injected new voltage, and that IC has a absolute maximum supply voltage of 6V (recommended "normal max" of 5.5V). Also note, that with this option, you'd also want to make sure to cut the PI ISO jumper.</p><p>Please be careful when attempting either of these options, because you can risk damaging your pi. I'd definitely recommend viewing the eagle files thoroughly and double-checking all your connections before powering it up and/or plugging it into your Pi.</p><p>Good luck and thanks for reaching out!</p></p>
Gumbercules on DEV-15316 - SparkFun Servo pHAT for Raspberry PiGumberculesurn:uuid:8b9cb4e1-5eb9-e75a-9635-83dd6d71bbf22020-05-01T09:57:11-06:00<p>Is there a way to use a higher voltage supply (6V-7.4V) for the servos? I assume you'd need to cut the isolation jumper and find a supply point to solder on to.</p>
santaimpersonator on DEV-15316 - SparkFun Servo pHAT for Raspberry Pisantaimpersonatorurn:uuid:d9ad131e-9cfb-fb5f-b44e-03b2c09cd8942019-07-16T11:21:18-06:00<p>You can configure the sub-addresses (<em>see <a href="https://cdn.sparkfun.com/assets/e/4/0/5/9/PCA9685.pdf" rel="nofollow">datasheet</a></em>). Although that is not the design intention for those addresses, but it should allow you to control up to (3) chips (<em>unfortunately, we don't have step-by-step instructions for that</em>). I am pretty sure 16 is the maximum channels offered, but if you find a better IC, let us know.<p>In this case, the hat was designed to be used with the <a href="https://www.sparkfun.com/products/15302" rel="nofollow">Sphero RVR kit</a>, so we have everything preassembled.</p></p>
Gumbercules on DEV-15316 - SparkFun Servo pHAT for Raspberry PiGumberculesurn:uuid:62b246f9-e2fa-7f3e-1815-6ad794d4e6e12019-07-16T09:45:06-06:00<p>Totally understandable, the layout looks great considering how much stuff is packed on there! I just wasn't sure if you were going to offer a header-less version like you do with other dev boards. I'll definitely keep an eye out for the Qwiic version. It's just unfortunate that these chips only offer 16 channels when a hexapod usually requires 18. Thanks!</p>
santaimpersonator on DEV-15316 - SparkFun Servo pHAT for Raspberry Pisantaimpersonatorurn:uuid:69de1492-ecd0-f1d6-f004-0596e02882fc2019-07-12T07:04:17-06:00<p>You are correct, the PCA9685 was originally designed for LED PWM control. However, <a href="https://learn.sparkfun.com/tutorials/hobby-servo-tutorial" rel="nofollow">servos</a> (<em>this doesn't control DC motors</em>) are controlled with PWM signals. Since the PCA9685 is capable of producing the proper PWM signals, it can be used to control the servos. (*I think I calculated the PWM resolution to equate to less than half a degree on a 90° servo; based on the datasheet.)</p>
santaimpersonator on DEV-15316 - SparkFun Servo pHAT for Raspberry Pisantaimpersonatorurn:uuid:e742e8b1-8082-efeb-af77-0bf70e43ae642019-07-12T06:57:19-06:00<p>I think we might be making a Qwiic version (with less channels???), but we will probably break out the address pins on that. I know that for this release, it was pretty tough just to squeeze all the components; especially with the RX switch and RVR, servo, and GPIO headers covering most of the real estate.<p>Unfortunately, we don't offer custom board manufacturing. Maybe a 3x20 pin right angle M/F header might be worth scouring the internet?</p></p>
santaimpersonator on DEV-15316 - SparkFun Servo pHAT for Raspberry Pisantaimpersonatorurn:uuid:3f00b4f8-a5be-aca4-b643-25745bec97aa2019-07-12T06:41:41-06:00<p>I think you meant to post this comment on this <a href="https://www.sparkfun.com/news/2958" rel="nofollow">blog</a>. Thanks for the heads up on the typo, I'll pass the information along.</p>
Gumbercules on DEV-15316 - SparkFun Servo pHAT for Raspberry PiGumberculesurn:uuid:738bf94d-da40-f920-5118-c2bdf6cbec252019-07-12T06:35:25-06:00<p>It's the same controller. It can be used as a generic PWM driver so it'll work for servos as well as LEDs.</p>
Gumbercules on DEV-15316 - SparkFun Servo pHAT for Raspberry PiGumberculesurn:uuid:071ca63e-581d-ed0e-9011-356ca1f20ae82019-07-12T06:15:54-06:00<p>Any chance of getting one of these with right angle servo headers and broken out address pins so that you can have multiple chained together?</p>
aBoogieman on DEV-15316 - SparkFun Servo pHAT for Raspberry PiaBoogiemanurn:uuid:c7f989b4-2133-e85d-47ca-8771631c0b772019-07-12T05:27:24-06:00<p>Also, on your Qwiic_Py documentation page, you definitely have a typo:<p>"The qwiic Python package current supports the following platforms:"</p><p>Should be <em>"... currently ...."</em></p><p>Edit: Do you guys need an editor? I'm pretty good at editing. See how much practice I get at it? :-)</p></p>
aBoogieman on DEV-15316 - SparkFun Servo pHAT for Raspberry PiaBoogiemanurn:uuid:1da254a8-abeb-0125-5604-b5cde8ce0d182019-07-12T05:01:00-06:00<p>Hey, sounds great!! I like the idea of being able to power stronger motors.<p>However, I think you've got the wrong datasheet linked. The PCA9685 (according to your current link) is a:
16-channel, 12-bit PWM Fm+ I2C-bus LED controller</p><p>We're not talking about LED controllers here. Or we're not supposed to be! :-)</p><p>So tell you what, if you'll fix the link, I'll delete this comment. (I.e., if I can.)</p><p>Thanks,
Leland...</p><p>Edit: Also, fix the document link, and I'll buy one right away!! Maybe two, if you fix it quickly enough! :-)</p><p>Edit 2: Or <em>is it</em> actually the same controller?? (And I was wrong above?) Maybe that's possible, given my current knowledge level. (Pun intended.) :-P</p></p>
Customer #1532643 on DEV-15316 - SparkFun Servo pHAT for Raspberry PiCustomer #1532643urn:uuid:ff7bdcd1-a785-efcd-9fab-02f7ae7645fa2019-07-11T22:21:41-06:00<p>Will this be able to control the Bolt without the need for the RVR at some point? What language is used to program the RVR using the pHat interface?</p>