Examples of CPLD and Microcontroller Companionship A CPLD does not always compete with a microcontroller. The following are se veral cases where the CPLD makes an excellent companion to a microcontroller. GPIO Pin Expansion In a common application known as general-purpose I/O pin expansion, many designers combine the programming. For the past several months I have been enjoying the for the AVR processors. In fact, this nearly zero dollar tool has proven so fascinating and useful that it got me wondering if it were possible to extend the concept to FPGA/CPLD development as well. (FPGA: Field Programmable Gate Array. CPLD: Complex Programmable Logic Device.) So I did a little digging on the web and came up with a development system for Atmel CPLDs. Comparison with Altera devices shows their pinout to be the same (within the restrictions I detail below), so they'll work also. By building the development board and interface cable I'll present, then downloading the tools, you can develop your own CPLD applications. Please note the following limitations and restrictions. I've tried to balance capability and simplicity so you can build something that you'll enjoy and learn from. 5V devices only. Extending the system to cover additional voltages (3.3V, 2.5V, 1.8V are supported by Atmel devices in the same family) is not difficult, but it complicates both the development board and the programming cable. Let's skip it for now. Note that you have to provide a 5V supply to the board. 44 pin PLCC only. Specifically, I've programmed the Atmel ATF1504AS. The Ghetto CPLD concept can be easily extended to other Atmel devices, but this device seemed like a good compromise between price, ease of use, and capability. The concept should also extend to other devices such as those from Altera, Xilinx, Actel, etc. In fact, the Max7000 family EPM7032 and EPM7064 will work in the same socket as long as you use the 44 pin PLCC versions. So far I've only used the Atmel programming cable, but the Altera Byte-Blaster is supported by the Atmel software and should also work fine. It's actually a little simpler design than the Atmel cable. (I built the Atmel version and it works, so I haven't tried the Altera version.) SparkFun offers a $15 version of the Altera cable. Since this will work for both Atmel and Altera, I recommend it. If you're going to develop with Altera parts, you'll want to get the Altera software as well. I haven't actually tried this, but there's no reason I can think of that it wouldn't work. Speed is limited. Since the Ghetto CPLD Development System is built with hand wiring and no ground plane, don't expect reliable operation at speeds over a few megahertz. Even that's not guaranteed your mileage may vary! Of course, if you build prototype hardware that has a ground plane then your CPLD may work just fine at higher speeds. Just don't expect it to go fast mounted in the Ghetto Development System. You'll need a 44 pin plcc socket, some decoupling caps, some unprogrammed CPLDs, sockets for breadboard connections, a pull-up resistor and maybe some perf board to build it on. If you have any of this in your junk box you can save a few bucks. For your convenience, here are Part Numbers: CONN PLCC SOCKET 44POS TIN PN: 1-822473-4-ND SOCKET IC OPEN FRAME 14POS.3' PN: 3M5462-ND Qty: 2 SOCKET IC OPEN FRAME 18POS.3' PN: 3M5464-ND Qty: 2 CAP ELECT 10UF 50V SU BI-POLAR PN: P1280-ND Qty: 1, C1 CAP CER.10UF 50V 20% DISC RAD PN: 478-4275-1-ND Qty: 4, C2-C5 RES METAL FILM 5.10K OHM 1/4W 1% PN: P5.10KCACT-ND PC BOARD FR4 1-SIDE PPH 4.0X4.0 PN: V2010-ND IC CPLD 64 MACROCELL 10NS 44PLCC PN: ATF1504AS-10JC44-ND A few parts may have minimum quantities, but should still be pretty cheap. If you want to build some blinkenlights (Step 8) or make a set of switches (step 9) you may want to order these also. Keep in mind that Digikey has a $25 minimum to avoid a handling charge, so you might want to get a couple of extra unprogrammed CPLDs or an AVR processor or two just for fun. I recommend you buy the Altera programming cable from. Here are the part numbers. Get the cable and connector as well. (Otherwise, order parts for the cable from Digikey if you're building your own.) Altera FPGA Compatible Programmer PN: PGM-08705 2x5 Pin IDC Ribbon Cable PN: PRT-08535 2x5 Pin Shrouded Header PN: PRT-08506. I'm currently using the Atmel Prochip Designer 5.0 tool chain. This tool requires that you register with and fill out their official request form. I told them I was a design engineer, currently unemployed, and my primary purpose was to learn their devices and VHDL (all true, BTW). They approved the license request. Which is the best weapon? Just remember to save often! It's hard to tell, speaking of SoC, pistols are weak and you will hardly find anyone using them, but you should not give up on them, they are light weight and as some casual game once said, is faster to change weapon rather than reload, while in AMK some latter ones will put down even the stronger mutant or human, the AS VAL by the statistics should be the best and is actually very good, but more than one Stalker found little problems finishing with just an AK variant or the SIG and the right ammo. Stalker call of pripyat gamedata folder options. You may find tons of free items, alternative routes and interesting things. Stick with the game. The only catch is that the license is good for only 6 months. I'm hoping to find a public domain tool chain by the time it expires. Altera also has a tool chain I may check out. Any suggestions will be appreciated. See comments and links in the last step. The Atmel Prochip Designer 5.0 is.
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