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Member #289967

Member Since: January 11, 2012

Country: United States

  • This is similar to a Picoblaze design project my lab partner, Nathan, and I did at Cal Poly SLO in Winter 2010 for our CPE269 course (Computer Design & Assembly Language Programming). We used a Xilinx FPGA (Spartan 3), with their PIcoblaze processor core, on a Digilent Nexys 2 dev board. We interfaced a Votrax SC-01 speech synth. Nathan came up with the idea of doing a binary code entry game. You would be given a random decimal value and had to use four switches to enter the BCD equivalent value of the number shown on a 7-segment display. Only did numbers between 0 and 9. You would place the switches in the right configuration (up was a 1 and down was a 0) and press a button to check your answer. The speech processor would say the number you entered, then state whether you got it right or wrong, then ask you to enter again if you got it wrong. Three wrong answers in a row would add the phrase "What are you, a business major?" We created a 8bit counter and a 256 byte ROM in the FPGA core using VHDL. The 256 byte ROM contained all of the phonemes for the phrases (lower 6bits were the speech data, bit 7 was set for the very last entry in the phrase). The code would load the address of the beginning of the speech phrase and enable the counter. The Votrax had the ability to self feed itself and clock the counter at its own pace. The very last byte generated an interrupt telling the Picoblaze code to disable the counter and load the address for a silence phoneme. That was a very fun project to do because I got to make use of one of my favorite chips - the Votrax SC-01. I originally tried to use the General Instruments SPO256 that I had found on a board from a thrift shop. But the voice quality on that chip was not as good as the Votrax - which I robbed from an Alien Group Voice Box used on the classic 8bit Atari computers.

No public wish lists :(