Savel brain dump in English!

I was planing big article about FPGA chips and was testing all circuits when suddenly connected on Altera Flex I/o pin to LCD bias power supply. This was the end of my Altera FLEX. Here is the picture of my workbench…:

Here you can see breadboard with power supply, ByteblasterMV programming cable, Altera Flex testing PCB with EPF10K10TC144-4 on board, rotary encoder, possible substitute for flex- Altera Cyclone II (EP2C5T144C6N) and VGA connector to old CRT monitor.

Just before the accident this all stuff generated such image on old CRT VGA monitor:

It is not my invention, I just used source code from the internet site. Only I changed a bit of the source to adapt it to my hardware and oscillator frequency. That blob on the middle of the screen is the “ball”. It bounces from all sides of monitor and from the paddle movable by rotary encoder.

So I decided to port all this stuff from CRT VGA to controlless LCD panel. But somehow I connected encoder’s ground pin to LCD bias (-15… -20V). This was great shock for FPGA chip and whole I/O bank was dead. The chip is very hot. Most interesting, that core is still working and I can see FPGA on JTAG chain. I don’t have any diagnostics software, but chip is reporting itself as damaged.

So, I am very sad and decided to suspend this project for some time. I ordered (and received- this blog entry is translation of Lithuanian blog and it is not “up-to real time”) chips from eBay for future experiments. Cyclone is working too, but it is soldered to custom PCB and I have only few I/O pins available for use.

I have Willem eprog programmer, but I was sick changing LPT cable each time I need to reprogram some chip. Also, Willem damaged two chips of one manufacturer. I don’t like that small DIP switches too. Also, Willem can’t program GAL chips.

So I searched the internet and eBay for some recent programmer. My wish list is small: USB, easy to use, GAL. And I found some Chinese made TOP series programmer. They are cheap, USB and jumper-less. Can they support CPLD? I found one in eBay, won, but didn’t pay. Next day I received message from eBay, that seller is fraud and all auctions are cancelled. Also, paypal told that all money will be returned. So, I found other seller with more feedback and ordered TOP2004 programmer again for 49.99 USD. The problem is, that package sending costs from Hong Kong is very expensive- 34 USD. The only good news that American dollars are cheap these days- I love inflation rate of USD. So I payed 218LTL 00 ct. and after about 3 weeks I received programmer. As good Chinese seller wrote in the documents that it is gift and valued on 13$, I don’t pay the VAT and customs fee.

I installed software, connected USB cable and everything is working. The only bad thing is that all messages in the software are written in so called chinglish language (like mine ). but I don’t care- my English is not pure too. But sometimes I have big smile from pop-up messages.

And now review about the programmer itself…
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Just short story about my experiments using CPLD chip and Lattice software.

I forced myself to use and learn about programmable logic chips. As I wrote in my older post, I have very small inventory of the chips and was forced to use Lattice isp2032VE110LT144 chip. I received great help reading article from Seattle Robotics Society web page. Also, at same time I was experimenting with controller-less LCD screen module. So I joined both ideas to one project and here is the result.

Also in this project is used my universal dual output power supply from older post.

The theory about LCD control was tested using big computer and MS Visual Basic software. CPLD programing software I downloaded from Lattice Semiconductors site. The chip was soldered to self-made testing PCB.

And now few words about programing of the CPLD devices…
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Very often I need regulated PSU when playing with breadboard. And I need negative power supply too. Especially when doing something with operational amplifiers or old LCD modules. Typically I use 78xx or 79xx regulators in my experiments. But last experiment was draining lots of power and 7805 was very hot. And I use wall adapters as my PSU. So if I need dual voltage, I need to use two adapters. Also, the regulators take too much place in the breadboard and are not very efficient. So I decided to build add-on for my breadboard.

Here is the result:

It is not a miracle It just old, refurbished LT1076 chips from some old video multiplexer (I found nice dual port RAM and fast ADC/DAC too…). One LT1076 is working as standard step-down regulator and other as inverting. All outputs are regulated using simple variable resistors (blue ones on PCB). The output of positive regulator is from Vin to 0V. Negative output is more wide- when I was using small 7.5V, 1A wall adapter I managed to get output from 0 to -25V (with low load).

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I decided to put all ISP/JTAG cable circuit diagrams (schematics) in one page for easy navigation. The schematics are gathered in the internet in various web pages and datasheets. Cables are not designed by me, but I made some of them and tested. These cables can be used to program various CPLD/FPGA chips and some Atmel AVR/ATMEGA mcus.

• Xilinx parallel III.
• AVR STK200.
• Xilinx JTAG.
• Altera ByteBlasterMV.
• AVRSP LPT.
• Lattice ISP.
• Lattice ISP. I made this one. It is working.
• STK200 ISP.
• Altera Byteblaster. I made this one too, but with small modification- I added addition 5V regulator and PSU connector. So I can power cable logic from external power supply. It is useful when programming 3V logic with 5V TTL tolerant pins.