GTP-USB-Lite Programmer re-flsahed as USBPICProg

I bought this programmer from local supplier a few years ago. This is a GTP-USB-lite programmer clone and beautifully build as sandwich  style.

USB-PIC_Prog (2)


USB-PIC_Prog (3)

Some drawbacks of this programmer are:

  • I noticed that this programmer don’t work with some PC/Laptop USB port for unknown reason.
  • Don’t support Windows 7
  • Not opensource,


Anyway, GTP-USB programmers are the best and DIY friendly at their age. Mostly, I used PicKit2, PICKit3 as main programmer. So, I leave this programmer in a corner of my desk for a while. Last week, I noticed a post in DP forum about hacking aka flashing this programmer.

The original blog post here.

At the last weekend, I try to flash my GTP-USB-Lite programmer with new firmware and to use new software. The procedure is very simple.

- GTP-USB-Lite and USBPICProg are very identical hardwares, USB interface, PIC18F2550, the same charge pump, same programming header’s pin.

- The difference are;

  • GTB-USB lite used 8MHz crystal and USBPICProg uses 12 MHz crystal
  • LEDs are connected at PIC pins 11,12 and 13 in USBPICProg and pins 27,28 at GTP-USB-Lite.

GTP-USB-Lite hardware circuit

USBPICProg hardware , firmware, PC software (The best thing is  all are opensource :D)

- First, to take off and flash programmer’s PIC18F2550 with boot loader and to change 12MHz crystal in circuit

USB-PIC_Prog (4)



- Download and installed PC software and install it.

- Download last firmware and  attached programmer. The PC will detect bootloader and install bootloader USB interface driver. Launch the PC programmer software and  bootloader is activated and update firmware.

- USBPICProg-0.6.0-software –> Updated Firmware

- Then, remove programmer from USB port. Connect PGC pin (RB6 , Pin No 27 of PIC18F2550) to ground to de-activated the bootloader and activated USBPICProg programmer mode. The PC USB port will detect and installed new device (USBPICProg) driver.

Before final launch, I simply cut the trace between LEDs and  RB7,RB6 (pin 27,28) and connected LED’s resistors to Pin 11,12. LED shows signal now.

USB-PIC_Prog (1)


For now, I can use reborn USBPICProg as a backup programmer. I renamed it USBPICProg because it is no more GTP-USB Lite.




Leave a comment

Filed under Message, PIC, Programmers

Microchip Advanced Parts Selector and other handy tools (Online/Offline/Mobile vers)

I used PIC as my primary development platform for years. Selecting a right MCU and checking features while developing is a time consuming task sometimes. Last week, I noticed handy tools in Microchip website.

The first tool is Microchip Advanced Parts Selector (MAPS) tool. There is online and also offline version. I tested both quickly. Online and offline version are same interface. Great, can search, filter and compare various PIC easily.

The link :


There is also a mobile version for both Android and IOS platforms named Mobile Product Selector.  It is also handy to use with your tablet at workbench while testing something.

Android App Link:


Wait, there are also some good tools for discrete components, Analog and Interface Products Presentation – (Offline Only). This is a power point file with good linking. You can click and find right info for interface , analog peripherals and  parts like transceiver, op-amps etc..


Last one is “Product Tables”, all PIC with required info and volume pricing can be downloaded as PDF or CVS format.

Leave a comment

Filed under Message, PIC

Visitor Hits Raise

It was a day of last month, waked up early morning, checked my blog. Usually, I don’t check my blog daily and sometimes once per week because there are not much visitors in my tiny blog. Also I cannot update my blog for a moment. But, my eyebrows raised. There was a site’s notification show that visitors status was more than usual. I checked status report. “More than 10000 visitors in a day”. What the hell is going on. Is wordpress domain under attacked?


I checked the traffic’s source quickly. Its come from “HackADay” and also from “Lifehacker”. I noticed the source of traffics. I am a fan of these two sites. Last year, I posted about my old laptop to All in one desktop conversion. This post was appeared in these sites and also in some several sites around.


Thanks “HackADay”, “Lifehacker” and all visitors for interesting this. Yes, recycling and reusing is good for all.

There is also another reason why I still use such old PIII laptop.

First reason, I don’t need much power for both hardware and software. Mostly, I used this for microcontroller and other circuits design development. So, I used MPLABX, Pickit2, Eagle etc. These software run well in old hardware with windows XP. And some of MCU and electronics tools work well in XP, not in windows 7.

Second reason is that this laptop is versatile. It has various IO ports, serial, lpt and usb. For serial COM port, using a hardware serial port is much convenience with some hardware like JDM programmer. And the LPT port, this is great for using CNC motor driver and handy for any hardware hacking liked JTAG and raw IO access from C++ program. Yes, it is the age of USB and LPT is not included in standard PC any more. For me, LPT is still handy interface for many case. It is fast, easy to access.

Third reason is cost effective for hardware testing. As you know, PC hardware interfacing with DUT is not a safe job. Your new model PC or laptop may blow up and consuming your pockets a lot at any time. Throwing old PC is not like this. I used this oldie for several years. It’s more than it’s price.

Leave a comment

Filed under Message

Bus Pirate Necktie Clip Case

Last year, I got Bus Pirate kit from Dangerousprototypes as a prize for last year 7400 competition. Thanks again DP. This is now an essential tool in by bench. It is not only BP. It came with a box, LCD back pack, test probe, lots of jumpers,.. a complete kit.



After getting BP, I try to make a case as usual. Mostly, I prefer acrylic style case like my OBLS and PICKit2. DP calls it “Sick of Begie” case. This time, I found out something which was suitable for the Bus Pirate case.

BusPirate_case (1)

Yes, a necktie clip case.

BusPirate_case (2)

GOOD, BP fits inside it.

BusPirate_case (3)

First, make holes for plastic snap-in fasteners.

BusPirate_case (4)

Second, filing the edge for USB cable connector.

BusPirate_case (6)

Then, make a rectangle for probe cable. And fitted the snap-in rivets.

BusPirate_case (7)



Finally, the case for BP was finished. It took about 15 minutes.


Filed under 7400 cmpetition, Bus Pirate, Custom Case, DIY

Hot-Air Rework Station Repairing

Last week, I switched on my hot-air station to do some soldering job. While I was doing other things, I smelled something. I noticed the smell is from hot-air nozzle. I switched off the station and checked that soldering nozzle is melted down due to overheat. Oop! what the hell is going on.

I quickly checked the problem. There is no air flow at the nozzle. But I still heard the air compressor  sound.


Hot air nozzle is melted down

Today, I tear down and find out the problem. My rework station is a cheap china made, LK852D brand. Here is what inside.

Hot Air rework station inside

Hot Air rework station inside

There are three boards, one step down transformer, one air compressor inside. There is nothing special, the right board is the controller board for hot-air nozzle and air pump controller. The left down side is the soldering gun controller. The left up side is a 7-segments display controller (3 digits display x 2 ).

hot air gun controller

hot air gun controller

This is hot nozzle controller and air pump controller. There are two Triacs, BTA136 , one for heat gun and one for air pump. There is also one IC, LM324 common opamp. The circuit is very simple. This is just Triac controller like a light dimmer. The Opamp LM324 is used to control Triac  with thermo-couple feedback, somehow comparator circuit like my previous soldering gun repair.

hot-airgun-repair (3)

LED Display and Soldering Iron controller

The upper circuit is 7-Segments display and the lower circuit is soldering iron driver. The 7-segment display driver IC is erased label. I don’t brother what’s inside these board for this moment.

The problem is the air compressor. There is no air flow. So, I removed the air pump outside the case and checked this. The controller of pump works well. The output voltage is measured and this can be controlled by the front panel knob. The noisy sound of compressor state that the driver is worked welled.

air pump take off



So, I open the pump by removing bottom side screw. This is diaphragm pump type. I quickly check that the both side rubber diaphragms are melted, leak  and damaged. Thus, the pump is not working well.

Air pump inside

Air pump inside


Damaged diaphrams

Damaged diaphragms


I cannot source locally the replacement part for this pump. But, I saw a guy is using aquarium pump in DIY hot-air gun.  The aquarium pump are also the same principle as the hot-air pump. Luckily,  I have this type of pump in hand. I bought this pump long ago to use with PCB etching tank but never use it. Good, now I have a good reason to use this.

aqurium pump


Opened the pump from down side, remove original AC cord and connected with driver output wires. This pump has dual output. I combine the two outputs easily to nozzle pipe like that. There is a air flow control switch beside the pump. I simply switch to high position.

Aquarium pump inside

Aquarium pump inside

replaced original AC cord and solder two wires

replaced original AC cord and solder two wires


Connect air pipes

Connect air pipes


Then sealed the two air output pipes inside the nozzle pipe with hot glue gun.

hot-airgun-repair (17)



hot-airgun-repair (18)

Attached the pump inside the case by cable ties.

Then, switched on and test the hot-air flow. It’s work. The hot air is flow out from heat element nozzle again.

hot-airgun-repair (19)



Finally results and  thought,

- The air flow is not strong as original compressor but it still work

- In most soldering case, the pump controller knob is required to set at 3/4 or 4/5 position. The air flow setting adjustment clearance is not so good.




Filed under DIY, Soldering

DIY PICKit-2 Lite

After some years in PIC development, I built and tested DIY programmers. Formerly, I used LPT classic Tratit style programmer. This programmer is very good and stable for most 16F and 18F PIC mid-range series. Later, LPT port is no more option in modern PC and Laptop. I found out serial port programmer and used JDM-2 for a moment. The problem of JDM and it’s style serial port programmer is that they are very buggy with USB-Serial adapter or even in some low power serial port laptop.

Here is my collection of constructed and tested DIY programmers along with my developments. One day, I may be write about these programmers, the good, the best and the urgly :D.


Finally, I considered to use USB programmer and constructed PicKit-2. This is Microchip original successful PIC programmer and compatible with almost all PIC line.

I consider to use Lite version of than original PicKit-2 design. The lite version is a strip down version of original kit-2 because most of original functions are not required for starter and hobbyists.

The main differences between original and lite version are :

- Lite ver don’t use eeprom because they are used only for OTG programming without PC

-Target voltage detection (3.3V and 5V) circuit is removed because most hobbyist stick on only 5V PIC

Since, the first use, I stick all with my PIC development and found that very stable and convenience to use. My design is based on Blueroom-electronics design. The Blueroon website is down now. This is the copy of PicKit-2 lite schematic from Blueroom.


I used BC547 and BC557 transistors in my build. For 680uH coil, I used a small filter coil from ATX power supply secondary output rail. Here is my construction.


For those who interested in 3.3 V target, here is modification of Felixls and Suky for 3.3V targets.

Pickit-2 lite can be used with original Microchip farmware and software without any problem. The resource can be found here.

Updated:  Chris point me out that schematic error, PIN-15 is D- and PIN-16 should be D+. I edited and uploaded correct diagram.


Filed under DIY, PicKit-2 Lite

DIY Old Laptop to All in One PC

I was busy with some tasks between past weeks. Unluckily, one of my development gear, old laptop was not in a good condition since a few weeks ago. It is a PIII laptop with 1GHz CPU and  loaded with my developments tools. I picked it up from disposal since three years ago. When I picked up this, battery was dead, motherboard was not boot, screen lids were broken.  I checked that mother board power supply capacitors leakage and replaced with new capacitors, fixed the screen lids with some epoxy, glues and heat gun. The old laptop was in service at that time. This laptop was manufactured from  infamous brand  Taiwan manufacturer but it’s performance was surprisingly good and stable. Now, it seem end of life again.

I love recycling and reusing things when there is possible. Is that good for environment and also for my pocket? :D

So, I started a weekend job to recover this hardware. Here is an original photo of this, screen lids and parts of body are broken. Some keys from keyboard are not respond and motherboard was unstable again.

My Idea is to transform this laptop as All in One PC by flipping installing LCD screen over body and making a base+mounting stand my self.

Laptop-2-AllinOne (1) Laptop-2-AllinOne (2)

Take apart all parts first. Removed battery, keyboard, mouse pad, up-side cover, floppy drive and CD drive.

Laptop-2-AllinOne (3) Laptop-2-AllinOne (4)

Up side cover with speakers, mouse pad.

Laptop-2-AllinOne (6)

Removed LCD screen from body.

Laptop-2-AllinOne (5)

Took off mother board to clean and to check.

Laptop-2-AllinOne (7)

The problem was the same as previous, leakage  capacitors at power supply. Replaced these capacitors and mother board is boot again. This is a common fault symptom of electronics devices especially manufactured about 2000 or cheapo ones.

Laptop-2-AllinOne (8)

Started hand-tools jobs.

Laptop-2-AllinOne (9)

Prepared down side cover holder. Reinforced with two metal flat sheets.

Laptop-2-AllinOne (10)

Finished down side cover with holders. Two L-shape aluminium support ware also installed at the side to fix LCD panel.

Laptop-2-AllinOne (17)

Took off LCD panel. I want to flip LCD panel and re-install it over the motherboard part to form like All in One PC. The LCD  connector cable was a little short to do this. So, the cable was took of and straighten and repacked again.

Laptop-2-AllinOne (11)

Laptop-2-AllinOne (12)

To seat LCD panel over down side cover, I installed L-shape aluminium stands at the back side of LCD cover.

Laptop-2-AllinOne (13)

Prepared the base and stand for mounting.

Laptop-2-AllinOne (14)

Panel mounting was finished.

Laptop-2-AllinOne (15)

The back installation of panel mount.

Laptop-2-AllinOne (16)

The first test assembly of down side cover and mount, base.

Laptop-2-AllinOne (18)

Re-installed motherboard, hard disk. Old battery, keyboard, Floppy and CD drive ware completely removed.

Laptop-2-AllinOne (19)

Speakers were re installed at new place (originally battery place).

Laptop-2-AllinOne (23)

First test assembly was finished. All in One style!!!

Laptop-2-AllinOne (20)


Back side of assembly. L-shape angles are used to attach LCD scree to base. A USB hub is attached and USB WiFi adapter is installed.


I bought a USB keyboard for re-branded PC.

Laptop-2-AllinOne (22)

Finally, the oldie classic PIII All in One PC is alive at my workbench. How a happy weekend hacking.

Laptop-2-AllinOne (25)



Laptop-2-AllinOne (28)

By the way, this is my last post of 2012.



Filed under Custom Case, DIY