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Well-Known Member
Thread starter #1
Ok im looking at this page:

and even on the ARM site has same info...

I though SWD was basically a 2 wire thing ? SWO and SWCLK and of course RESET and POWER PINS... so whats with


? i know to use SWDCLK but which one of the other 2 do i use ?

SWO or SDWIO ? i bet its the SDWIO but not sure and dont want to make a PCB for nothing :D


Well-Known Member
Ground 3, 5, 7, and 9. Connect 6 (SWO) to 3.3V with resistor (pull up). Leave 8 floating. Pullup reset. I've been using a reset supervisor as well, but not really needed.


Well-Known Member
Thread starter #5
ok so far i think im done. I have to send this PCB to get made now :) going to wait until monday tho. just in case i read something and want to add or remove something :D

I added a UART to USB (CP2102) IC and will use solder jumpers to connect the RX,TX lines .. just in case i dont use them i can desolder it...



Well-Known Member
Thread starter #6
:) i get bored as you can tell... i added a MMA7660FC which is a 3-Axis Orientation/Motion Detection Sensor or as we all know it "XYZ-AXIS ACCELEROMETER"

Also a reset button. I also fixed the SWD... i forgot to connect the ground and stuff :D

Also i uploaded the schematic and board file in Eagle Format for those who want it...



Well-Known Member
Thread starter #12
Ah! cool. I have no use for that kind of toy but seems cool!

By any chance you think this is a popular ST IC ? Talking about the STM32F103CB .... its about $10... i know pricy! but looks like it has tons of features including remapping and stuff... like 7 DMA channels i think.. its cool... I ask because when i send to make this PCB i get 3 of them as a set. So i will have 2 extra. I wouldnt mind selling the others or actually populating them and selling it like that.

Not sure if it would just be a waste tho
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Well-Known Member
Thread starter #15
Hey Mark im making a PCB for some of my LPC mcu's what would you recommend on it besides the normal


SWD Adapter
Complete Pin Outputs
Crystal and Caps
Power LED
USB (it has it available) Might use it just for power and solder jumper if want to connect to mcu


Well-Known Member
My breakout board for MCU's are bare bones. My LPC1752 has the most stuff on it, just because it has more peripherals. USB, CAN, and a 32k timer crystal, otherwise I don't put anything on the board that I already have another breakout for.


Well-Known Member
Thread starter #17
I try my best to minimize breadboard usage. If i can fit it on a PCB it will go in :D
I just noticed the LPC1313 isnt the USB version which is fine. I added a CP2102 for USB connectivity. Might just take your advice and leave it bare with only SWD and CAPS and some nice LABELS for the names heh

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