Powered by Invision Power Board

Forum Rules Forum Rules (Please read before posting)
  Reply to this topicStart new topicStart Poll

> Schematic For 8051 Modules ?, Looking for schematic
Posted: May 11, 2017 07:44 am
Reply to this postQuote Post


Group: Members+
Posts: 22
Member No.: 35,350
Joined: July 09, 2011

I'm interested in buying a few small microcontroller development boards to use in my general projects. I've always build my projects from scratch and figured I'd save time and money by using a pre-built board as a starting point.

The problem is I am stuburn and I believe it's really useful to have a schematic of the board I would be using. I know, really stupid, what would I do with a schematic.

Anyways, the boards I'm looking at - on Ebay - use the C8051F300 and the C8051F340. Wouldn't you know it none of the listings include a schematic. I've sent questions to over a dozen sellers - about two weeks ago - and got back a few responses - all of them saying they have no information at all on the item. These guys are all in China somewhere. Found a US seller (asking 3x as much) but he also has no clue.

So, I'm hoping one of you might know where I can get a schematic for one of these boards. The small one is for the C8051F300 - and has the text "CJMCU-8051" on the back. The larger uses the C8051F340, and seriously, I have not found any picture of it that shows any text that might be useful.

user posted image
user posted image

This post has been edited by dxpwny on May 11, 2017 07:47 am
PMEmail Poster
Posted: May 11, 2017 09:41 pm
Reply to this postQuote Post

Forum Addict ++

Group: Cleanup Taskforce
Posts: 2,468
Member No.: 4,841
Joined: April 16, 2006

If they are only 2-sided, it may not be too difficult to just follow the traces
PMEmail PosterUsers WebsiteYahoo
Posted: May 11, 2017 09:46 pm
Reply to this postQuote Post

Forum Addict ++
Group Icon

Group: Moderators
Posts: 20,594
Member No.: 73
Joined: July 24, 2002

Looks pretty obvious, from the pictures... a whole side of pins is fanned out onto headers, and a couple devices are tacked on where they go (dedicated clock, serial, etc. pins).

Maybe a sharp enough picture to see the IC part numbers, so you can look up their datasheets, would help?

Is this really going to break the bank so hard that 1. you have to order your dev kits from China and 2. you can't afford to just spam a dozen different ones to get one that works?


Answering questions is a tricky subject to practice. Not due to the difficulty of formulating or locating answers, but due to the human inability of asking the right questions; a skill that, were one to possess, would put them in the "answering" category.
PMEmail PosterUsers Website
Posted: May 23, 2017 05:59 am
Reply to this postQuote Post

Forum Addict ++

Group: Spamminator Taskforce
Posts: 1,053
Member No.: 3,131
Joined: August 29, 2005

Have you tried the Siliconlabs website?
I've designed with both of those parts before and the development kits always contain a board schematic.



There are only 11 pins on the '300, you can probably work out that schematic just from visual inspection.

Good luck.
PMEmail Poster
0 User(s) are reading this topic (0 Guests and 0 Anonymous Users)
0 Members:

Topic Options Reply to this topicStart new topicStart Poll


:: support us ::

ElectronicsSkin by DutchDork & The-Force