From: David S. <dav...@nt...> - 2006-05-19 20:56:12
|
Hi, We're going to be creating a custom pcb to mount our gumstix along with a couple of sensors which are just hanging off our STUART board with loose wires for testing atm. Most of the STUART board is surplus to requirements for the final design and I was wondering if anyone could confirm whether any of the components on the STUART board are required for what we need: - Power (coming from a 5V regulated source) - Pin 18 (20 pin GPIO layout) used for a PWM signal - I2C (SDA/SCL - Pins 1 & 3 on 20 pin GPIO layout) Or can we just simply use the STUART brd file as a guide and layout just these pins from the hirose connector? Thanks in advance Dave |
From: Dave H. <dhy...@gm...> - 2006-05-20 00:24:49
|
Hi Dave, > We're going to be creating a custom pcb to mount our gumstix along with a > couple of sensors which are just hanging off our STUART board with loose > wires for testing atm. Most of the STUART board is surplus to requiremen= ts > for the final design and I was wondering if anyone could confirm whether = any > of the components on the STUART board are required for what we need: > > - Power (coming from a 5V regulated source) > - Pin 18 (20 pin GPIO layout) used for a PWM signal > - I2C (SDA/SCL - Pins 1 & 3 on 20 pin GPIO layout) > > Or can we just simply use the STUART brd file as a guide and layout just > these pins from the hirose connector? Pretty much. The components on the STUART board are for a couple of purposes: 1 - USB support 2 - Serial port support. 3 - Voltage regulator to provide 3.3v for 1 & 2. If you don't need serial or USB, then none of the circuitry on the STUART board is required (except for the pullup resistor on the FFUART RxD line). --=20 Dave Hylands Vancouver, BC, Canada http://www.DaveHylands.com/ |
From: David S. <dav...@nt...> - 2006-05-20 18:35:32
|
Well that's good news. So even if I'm not using FFUART in any way I still need to include this = pull up resistor? Cheers Dave -----Original Message----- From: gum...@li... [mailto:gum...@li...] On Behalf Of Dave = Hylands Sent: 20 May 2006 01:25 To: gum...@li... Subject: Re: [Gumstix-users] Simple custom board design question Hi Dave, > We're going to be creating a custom pcb to mount our gumstix along = with a > couple of sensors which are just hanging off our STUART board with = loose > wires for testing atm. Most of the STUART board is surplus to requirements > for the final design and I was wondering if anyone could confirm = whether any > of the components on the STUART board are required for what we need: > > - Power (coming from a 5V regulated source) > - Pin 18 (20 pin GPIO layout) used for a PWM signal > - I2C (SDA/SCL - Pins 1 & 3 on 20 pin GPIO layout) > > Or can we just simply use the STUART brd file as a guide and layout = just > these pins from the hirose connector? Pretty much. The components on the STUART board are for a couple of purposes: 1 - USB support 2 - Serial port support. 3 - Voltage regulator to provide 3.3v for 1 & 2. If you don't need serial or USB, then none of the circuitry on the STUART board is required (except for the pullup resistor on the FFUART RxD line). --=20 Dave Hylands Vancouver, BC, Canada http://www.DaveHylands.com/ ------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, = security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache = Geronimo http://sel.as-us.falkag.net/sel?cmd=3Dk&kid=120709&bid&3057&dat=121642 _______________________________________________ gumstix-users mailing list gum...@li... https://lists.sourceforge.net/lists/listinfo/gumstix-users --=20 No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.1.392 / Virus Database: 268.5.6/339 - Release Date: 5/14/2006 |
From: Dave H. <dhy...@gm...> - 2006-05-20 18:53:23
|
Hi Chris, On 5/20/06, David Scanlan <dav...@nt...> wrote: > Well that's good news. > > So even if I'm not using FFUART in any way I still need to include this p= ull > up resistor? Yes - without it, you may drop into u-boot and never get linux booted up. Pulling it up puts it in the "idle" state, which is how it would be if all of the hardware was connected and nobody was sending data. --=20 Dave Hylands Vancouver, BC, Canada http://www.DaveHylands.com/ |
From: David S. <dav...@nt...> - 2006-05-20 19:20:05
|
Cool,=20 So if I stick a 2k ohm pull up on that that should be ok? Sorry I'm not = much of a hardware person! Aside from that could anyone point me in the right direction for the = part or library in eagle for the 60 pin hirose part used on the STUART board (ie = not the male part on the gumstix), cheers Dave -----Original Message----- From: gum...@li... [mailto:gum...@li...] On Behalf Of Dave = Hylands Sent: 20 May 2006 19:53 To: gum...@li... Subject: Re: [Gumstix-users] Simple custom board design question Hi Chris, On 5/20/06, David Scanlan <dav...@nt...> wrote: > Well that's good news. > > So even if I'm not using FFUART in any way I still need to include = this pull > up resistor? Yes - without it, you may drop into u-boot and never get linux booted up. Pulling it up puts it in the "idle" state, which is how it would be if all of the hardware was connected and nobody was sending data. --=20 Dave Hylands Vancouver, BC, Canada http://www.DaveHylands.com/ ------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, = security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache = Geronimo http://sel.as-us.falkag.net/sel?cmd=3Dk&kid=120709&bid&3057&dat=121642 _______________________________________________ gumstix-users mailing list gum...@li... https://lists.sourceforge.net/lists/listinfo/gumstix-users --=20 No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.1.392 / Virus Database: 268.5.6/339 - Release Date: 5/14/2006 |
From: Dave H. <dhy...@gm...> - 2006-05-20 20:32:12
|
Hi Dave, > So if I stick a 2k ohm pull up on that that should be ok? Sorry I'm not m= uch > of a hardware person! 2k seems kind of low. 10k is more typical. 20k or 47k would also be fine. Higher resistances mean lower current draw. With modern CMOS, you can use 100k and be fine. The 10k is a carry over from the TTL days. --=20 Dave Hylands Vancouver, BC, Canada http://www.DaveHylands.com/ |
From: David S. <dav...@nt...> - 2006-05-26 18:40:21
|
Hmm I think I may have made a booboo! OK so it doesn't work! In trying to find the problem I noticed I have = left GND@7 and NRESET unconnected on my hirose connector. Could this be why = I cant connect to my Gumstix? I don't have a serial port on the custom PCB so cant even see if its booting! All I know is usually it will pair with my PC via Bluetooth automatically and I can ssh in...which I can't, and also the light on my Bluetooth dongle doesn't go on constant as it normally would. I have connected all the other V_bats and GNDs, and also pulled up the FFUART RXD so it shouldn't drop into Uboot. Does anyone have any other ideas...are there any other pins I should = have connected from the Hirose 60-pin connector. Where can I probe to check = the gumstix is on? Cheers Dave -----Original Message----- From: gum...@li... [mailto:gum...@li...] On Behalf Of Dave = Hylands Sent: 20 May 2006 21:32 To: gum...@li... Subject: Re: [Gumstix-users] Simple custom board design question Hi Dave, > So if I stick a 2k ohm pull up on that that should be ok? Sorry I'm = not much > of a hardware person! 2k seems kind of low. 10k is more typical. 20k or 47k would also be fine. Higher resistances mean lower current draw. With modern CMOS, you can use 100k and be fine. The 10k is a carry over from the TTL days. --=20 Dave Hylands Vancouver, BC, Canada http://www.DaveHylands.com/ ------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, = security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache = Geronimo http://sel.as-us.falkag.net/sel?cmd=3Dk&kid=120709&bid&3057&dat=121642 _______________________________________________ gumstix-users mailing list gum...@li... https://lists.sourceforge.net/lists/listinfo/gumstix-users --=20 No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.1.392 / Virus Database: 268.5.6/339 - Release Date: 5/14/2006 |
From: Dave H. <dhy...@gm...> - 2006-05-26 19:50:11
|
> OK so it doesn't work! In trying to find the problem I noticed I have le= ft > GND@7 and NRESET unconnected on my hirose connector. Could this be why I > cant connect to my Gumstix? Do you have a tweener? Missing one ground with the others connected up should be fine (but it depends on the exact circuit on the gumstix side). All you should need is the pullup resistor on FFRXD and the gumstix should = boot. --=20 Dave Hylands Vancouver, BC, Canada http://www.DaveHylands.com/ |
From: David S. <dav...@nt...> - 2006-05-26 20:09:54
|
No I don't have a tweener. Just the gumstix and my board. Is there a = way I can check that the gumstix is on? A bit like having the light on the = STUART board (but obviously not quite!) Cheers Dave -----Original Message----- From: gum...@li... [mailto:gum...@li...] On Behalf Of Dave = Hylands Sent: 26 May 2006 20:50 To: gum...@li... Subject: Re: [Gumstix-users] Simple custom board design question > OK so it doesn't work! In trying to find the problem I noticed I have left > GND@7 and NRESET unconnected on my hirose connector. Could this be = why I > cant connect to my Gumstix? Do you have a tweener? Missing one ground with the others connected up should be fine (but it depends on the exact circuit on the gumstix side). All you should need is the pullup resistor on FFRXD and the gumstix = should boot. --=20 Dave Hylands Vancouver, BC, Canada http://www.DaveHylands.com/ ------------------------------------------------------- All the advantages of Linux Managed Hosting--Without the Cost and Risk! Fully trained technicians. The highest number of Red Hat certifications = in the hosting industry. Fanatical Support. Click to learn more http://sel.as-us.falkag.net/sel?cmd=3Dk&kid=107521&bid$8729&dat=121642 _______________________________________________ gumstix-users mailing list gum...@li... https://lists.sourceforge.net/lists/listinfo/gumstix-users --=20 No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.1.392 / Virus Database: 268.7.2/349 - Release Date: 5/26/2006 |
From: Dave H. <dhy...@gm...> - 2006-05-26 20:49:52
|
On 5/26/06, David Scanlan <dav...@nt...> wrote: > No I don't have a tweener. Just the gumstix and my board. Is there a wa= y I > can check that the gumstix is on? A bit like having the light on the STU= ART > board (but obviously not quite!) I was just thinking that with a Tweener you could verify that the gumstix boots (by watching the serial port). You should see some toggling on the FFTXD line as uboot prints out it's messages. The FFTXD line should otherwise be idling at 3.3v. Which would indicate the gumstix is powered. --=20 Dave Hylands Vancouver, BC, Canada http://www.DaveHylands.com/ |
From: David S. <dav...@nt...> - 2006-05-26 21:07:50
|
Hmm...for some reason the FFRXD is pulled up to 5V, This wouldn't this affect it, would it? Unfortunately I can't really get to the FFTXD line when the gumstix is inserted as its one of the tracks I haven't implemented. Thanks for the continued suggestions. -----Original Message----- From: gum...@li... [mailto:gum...@li...] On Behalf Of Dave = Hylands Sent: 26 May 2006 21:50 To: gum...@li... Subject: Re: [Gumstix-users] Simple custom board design question On 5/26/06, David Scanlan <dav...@nt...> wrote: > No I don't have a tweener. Just the gumstix and my board. Is there a = way I > can check that the gumstix is on? A bit like having the light on the STUART > board (but obviously not quite!) I was just thinking that with a Tweener you could verify that the gumstix boots (by watching the serial port). You should see some toggling on the FFTXD line as uboot prints out it's messages. The FFTXD line should otherwise be idling at 3.3v. Which would indicate the gumstix is powered. --=20 Dave Hylands Vancouver, BC, Canada http://www.DaveHylands.com/ ------------------------------------------------------- All the advantages of Linux Managed Hosting--Without the Cost and Risk! Fully trained technicians. The highest number of Red Hat certifications = in the hosting industry. Fanatical Support. Click to learn more http://sel.as-us.falkag.net/sel?cmd=3Dk&kid=107521&bid$8729&dat=121642 _______________________________________________ gumstix-users mailing list gum...@li... https://lists.sourceforge.net/lists/listinfo/gumstix-users --=20 No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.1.392 / Virus Database: 268.7.2/349 - Release Date: 5/26/2006 |