Thursday, March 28, 2013

Raspberry Pi Rev 2.0 Pin headers

Got my new Raspberry Pi mode-B rev 2.0 yesterday.  After looking around the info about some new unpopulated through holes on it, finally I got all the info.  Here's the summary:

Silkscreen label: P2
It is a 1x8-pin connection for JTAG to the main SoC (Broadcom MCU).
Silkscreen label: P3
It is 1x7 pins to be used for JTAG header connected to the USB hub + ethernet chip.
Silkscreen Label: P5
2x4 pins.  It's for extra connection
Pin 1 (square solder plate): +5 V output
Pin 2: +3.3v
Pin 3: GPIO28 (can be configured as I2C's SDA)
Pin 4: GPIO29 (can be configured as I2C's SCL)
Pin 5: GPIO30 
Pin 6: GPIO31 
Pin 7 and 8: Ground

Silkscreen label: P6
1x2 pins.  For MCU reset (short them will reset the MCU)

By the way, here is the info about the board (I have no idea my the Hardware below shows BCM2708, not BCM28xx):

pi@raspberrypi ~ $ cat /proc/cpuinfo
Processor    : ARMv6-compatible processor rev 7 (v6l)
BogoMIPS    : 464.48
Features    : swp half thumb fastmult vfp edsp java tls
CPU implementer    : 0x41
CPU architecture: 7
CPU variant    : 0x0
CPU part    : 0xb76
CPU revision    : 7

Hardware    : BCM2708
Revision    : 000e
Serial      : 00000000xxxxxxxx



Thursday, February 28, 2013

My SMT Soldering result

Using X-Tronic hot air iron station, I was able to solder some ssop ICs (mostly the tiny ms430 microcontrollers) to their breakout pcb. The ICs are free samples from Texas Instrements.

Not bad for such small devices. Look professional to me.





Monday, February 25, 2013

Microsoft Empire



Found this diagram somewhere on the Internet.  As it is said on the top, it is permitted to repost here.  Very true and interesting!