# 2 Connected GigaBlox Rugged working problem in 100 Mbps link speed **URL:** \ **Category:** BotBlox Hardware\ **Tags:** gigablox, gigablox-rugged\ **Created:** [January 16, 2025, 11:12am UTC](https://forum.botblox.org/t/2-connected-gigablox-rugged-working-problem-in-100-mbps-link-speed/370 "2025-01-16T11:12:41Z")\ **Posts on this page:** 15\ **Page:** 1
**Author:** ![recep](https://avatars.discourse-cdn.com/v4/letter/r/45deac/32.png) [@recep](https://forum.botblox.org/u/recep)\ **Post date:** [January 16, 2025, 11:12am UTC](https://forum.botblox.org/t/2-connected-gigablox-rugged-working-problem-in-100-mbps-link-speed/370/1 "2025-01-16T11:12:41Z")
Hi, I bought 2 GigaBlox Rugged board because i need 5-port for custom hardware project. I connected port-1 on both boards to each other and it worked. I want the ports to operate at 100 Mbps so i connected 2 twisted pair ethernet cable which is not support for 1 Gbps. It did not work in this configuration. I programmed registers for 100 Mbps but it did not work. What should i do? How can i operate 2 GigaBlox Rugged board for 5-port in 100 Mbps speed? ---
**Author:** ![josh\_elijah](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.botblox.org/josh_elijah/32/568_2.png) [@josh\_elijah](https://forum.botblox.org/u/josh_elijah)\ **Post date:** [January 16, 2025, 10:10pm UTC](https://forum.botblox.org/t/2-connected-gigablox-rugged-working-problem-in-100-mbps-link-speed/370/2 "2025-01-16T22:10:12Z")
What do you mean “you programmed registers for 100Mbps”? There are no available registers on GigaBlox Rugged to program. Also, just curious, but why would you want to restrict the link between two GigaBlox Rugged to 100Mbps? A 1000Mbps link between both would only be beneficial, but maybe I’m missing something about your application. ---
**Author:** ![peci1](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.botblox.org/peci1/32/32_2.png) [@peci1](https://forum.botblox.org/u/peci1)\ **Post date:** [January 17, 2025, 5:52am UTC](https://forum.botblox.org/t/2-connected-gigablox-rugged-working-problem-in-100-mbps-link-speed/370/3 "2025-01-17T05:52:46Z")
Just to add: you won’t downgrade other ports to 100 Mbps by interconnecting the two switches at 100 Mbps. ---
**Author:** ![recep](https://avatars.discourse-cdn.com/v4/letter/r/45deac/32.png) [@recep](https://forum.botblox.org/u/recep)\ **Post date:** [January 17, 2025, 2:09pm UTC](https://forum.botblox.org/t/2-connected-gigablox-rugged-working-problem-in-100-mbps-link-speed/370/4 "2025-01-17T14:09:26Z")
Sorry it was my fault, i mean that i programmed vsc7511 (ethernet switch chip) registers for 100Mbps link speed. In my application i will connect 2 twisted pair ethernet cable so i cannot reach 1000Mbps. I solved my problem. When i write “O 1 0x0 0x2100” command in uart i forced port-1 for 100Mbps and both gigablox worked 100Mbps together. Thanks for your interest. ---
**Author:** ![recep](https://avatars.discourse-cdn.com/v4/letter/r/45deac/32.png) [@recep](https://forum.botblox.org/u/recep)\ **Post date:** [January 17, 2025, 2:12pm UTC](https://forum.botblox.org/t/2-connected-gigablox-rugged-working-problem-in-100-mbps-link-speed/370/5 "2025-01-17T14:12:08Z")
Yes, you are right. When i write “O 1 0x0 0x2100” (this command is just for port-1) command in uart i can force the ports for 100Mbps link speed. Both gigablox worked 100Mbps together. Thanks for your interest. ---
**Author:** ![josh\_elijah](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.botblox.org/josh_elijah/32/568_2.png) [@josh\_elijah](https://forum.botblox.org/u/josh_elijah)\ **Post date:** [January 17, 2025, 2:12pm UTC](https://forum.botblox.org/t/2-connected-gigablox-rugged-working-problem-in-100-mbps-link-speed/370/6 "2025-01-17T14:12:15Z")
Oh, you used the UART port to program the VSC7511?. How did you do that, there isn’t a UART port on the board. ---
**Author:** ![recep](https://avatars.discourse-cdn.com/v4/letter/r/45deac/32.png) [@recep](https://forum.botblox.org/u/recep)\ **Post date:** [January 17, 2025, 2:16pm UTC](https://forum.botblox.org/t/2-connected-gigablox-rugged-working-problem-in-100-mbps-link-speed/370/7 "2025-01-17T14:16:11Z")
Yes i can reach vsc7511 phy registers via uart. Thanks to “GigaBlox Rugged DataSheet C\_E .docx” document i saw the uart test points. ---
**Author:** ![josh\_elijah](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.botblox.org/josh_elijah/32/568_2.png) [@josh\_elijah](https://forum.botblox.org/u/josh_elijah)\ **Post date:** [January 17, 2025, 2:26pm UTC](https://forum.botblox.org/t/2-connected-gigablox-rugged-working-problem-in-100-mbps-link-speed/370/8 "2025-01-17T14:26:36Z")
There is no mention of phy registers in the datasheet? > **[GigaBlox%20Rugged%20DataSheet%20C\_E\_R.pdf](https://store-l0hv1zrcre.mybigcommerce.com/content/GigaBlox%20Rugged%20DataSheet%20C_E_R.pdf)** Which test points on the board, are you using, is it TP6 and TP7? ![Screenshot 2025-01-17 at 14.26.04](https://canada1.discourse-cdn.com/flex027/uploads/botblox1/original/1X/270537dfeb6fbab1c8229cc0aa8fa946b9d799ab.png) ---
**Author:** ![recep](https://avatars.discourse-cdn.com/v4/letter/r/45deac/32.png) [@recep](https://forum.botblox.org/u/recep)\ **Post date:** [January 17, 2025, 2:46pm UTC](https://forum.botblox.org/t/2-connected-gigablox-rugged-working-problem-in-100-mbps-link-speed/370/9 "2025-01-17T14:46:12Z")
I looked at the vsc7511 register map document to access the phy/mac registers. You are right, I am using the test points you marked for uart. ---
**Author:** ![josh\_elijah](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.botblox.org/josh_elijah/32/568_2.png) [@josh\_elijah](https://forum.botblox.org/u/josh_elijah)\ **Post date:** [January 17, 2025, 5:42pm UTC](https://forum.botblox.org/t/2-connected-gigablox-rugged-working-problem-in-100-mbps-link-speed/370/10 "2025-01-17T17:42:46Z")
Very cool, and actually something we haven’t tried yet. Can you confirm which guide from Microchip you’re using? We’ll test it here and potentially write up an official guide on that. Then, if that works well, we might make a new version of the board (revision D) that breaks out the UART pins on a proper connector for easy access. ---
**Author:** ![recep](https://avatars.discourse-cdn.com/v4/letter/r/45deac/32.png) [@recep](https://forum.botblox.org/u/recep)\ **Post date:** [January 17, 2025, 6:05pm UTC](https://forum.botblox.org/t/2-connected-gigablox-rugged-working-problem-in-100-mbps-link-speed/370/11 "2025-01-17T18:05:01Z")
Of course, you can download “VSC7511\_Data-sheet\_DS60001801A” document which is available in microchip web-site: > **[VSC7511](https://www.microchip.com/en-us/product/vsc7511)** > > Microchip's industrial Ethernet switch device delivers the industry’s lowest power Gigabit Ethernet (GbE) switching solution. The VSC7511 is a fully-integrated 4-port Gb Ethernet switch with four copper PHYs or four SGMIIs in a single... In this datasheet there is an embedded document for “VSC7511\_Registers” which is under the “Registers” section. I looked at the registers addresses in this document. Also, you can look “ENT-AN1199 Application Note Ocelot Unmanaged Software”. I found this document very helpful for understanding how to read and write commands to registers and it is very helpful for understanding software architecture. ---
**Author:** ![josh\_elijah](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.botblox.org/josh_elijah/32/568_2.png) [@josh\_elijah](https://forum.botblox.org/u/josh_elijah)\ **Post date:** [January 17, 2025, 6:29pm UTC](https://forum.botblox.org/t/2-connected-gigablox-rugged-working-problem-in-100-mbps-link-speed/370/12 "2025-01-17T18:29:53Z")
Thanks. I’ll set aside some time to check that out. We’ll see if we can mainline this into the functionality of an updated version of GigaBlox Rugged. If that happens, we’ll get some free samples out for you to test with. ---
**Author:** ![recep](https://avatars.discourse-cdn.com/v4/letter/r/45deac/32.png) [@recep](https://forum.botblox.org/u/recep)\ **Post date:** [January 17, 2025, 6:32pm UTC](https://forum.botblox.org/t/2-connected-gigablox-rugged-working-problem-in-100-mbps-link-speed/370/13 "2025-01-17T18:32:38Z")
Thanks for your interest. I will be happy to test it 🙂 ---
**Author:** ![josh\_elijah](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.botblox.org/josh_elijah/32/568_2.png) [@josh\_elijah](https://forum.botblox.org/u/josh_elijah)\ **Post date:** [March 12, 2025, 5:32pm UTC](https://forum.botblox.org/t/2-connected-gigablox-rugged-working-problem-in-100-mbps-link-speed/370/14 "2025-03-12T17:32:50Z")
We just tried this, indeed it works. ![image](https://canada1.discourse-cdn.com/flex027/uploads/botblox1/original/1X/4c644a084fc32fda2815976bf007a8d1a727649a.png) It gives a very simple interface, writing and reading to raw registers which means this would only be suitable for advanced uses, but it means access to all the registers is indeed possible on GigaBlox Rugged. Looking through the register map I can see there’s many settings, probably most of them are not useful. Stuff like port status and VLAN is there though, which is nice. There’s also pre-built commands for viewing port status and setting up Link Aggregation which is also nice. I’ve attached both the register map and the application note for accessing the UART port below. > **[VSC7511\_Registers.pdf](https://drive.google.com/file/d/1136EIvJhn0skOpKVStfpisxHnIVSydlj/view?usp=sharing)** > > Google Drive file. > **[VPPD-04413\_AN.pdf](https://drive.google.com/file/d/1-pQrQpAii3zpBVSs4KJT4Q9IhjqdbBzD/view?usp=sharing)** > > Google Drive file. This is a nice easy win, we’ll add a UART connector and release a new version of GigaBlox Rugged (BB-GGR-D-1) (revision D). ---
**Author:** ![recep](https://avatars.discourse-cdn.com/v4/letter/r/45deac/32.png) [@recep](https://forum.botblox.org/u/recep)\ **Post date:** [March 12, 2025, 7:11pm UTC](https://forum.botblox.org/t/2-connected-gigablox-rugged-working-problem-in-100-mbps-link-speed/370/15 "2025-03-12T19:11:30Z")
Happy for new version! Yes, you are right this register access for advanced users. I used it because I needed it for a specific project I was working on. Additionally, the VSC7511 software is open-source and can be found on Microchip’s GitHub account. For my project, I modified this software by adding custom print functions and some configurations about forcing link speed.