Hi ,i like to use cpld and fpgas scraped by boards at home at the purpose of practicing VHDL. I have some Spartan 3 XC3S1500,and an inexpensive Digilent JTAG cable rated 1.8 to 5.5 V. There is some trick to use it for programming a Spartan 3 ,having a core voltage of 1,2V? Thanks Diego,Italy
May i program a Spartan 3 fpga with a 1,8 V Digilent cable?
Started by ●November 6, 2007
Reply by ●November 6, 20072007-11-06
On Nov 6, 6:20 am, "blisca" <bliscachiocciolinatiscali.it> wrote:> Hi ,i like to use cpld and fpgas scraped by boards at home at the purpose of > practicing VHDL. > I have some Spartan 3 XC3S1500,and an inexpensive Digilent JTAG cable > rated 1.8 to 5.5 V. > There is some trick to use it for programming a Spartan 3 ,having a core > voltage of 1,2V? > Thanks > Diego,ItalyThe programming cable does not interface to the core voltage of the FPGA, only the I/O voltage for the JTAG. In some parts this is a separate JTAG or Auxiliary supply voltage. On other parts it may be Vcco for a particular bank. Usually it is in the range of 1.8 to 3.3V so there is no issue with the Digilent cable in this regard. I'm not familiar with the Digilent cable, but the Xilinx parallel cables have a pin for the interface voltage usually labelled Vcc that must be connected to the I/O voltage of the devices to be programmed. HTH, Gabor
Reply by ●November 6, 20072007-11-06
Gabor <gabor@alacron.com> wrote in message 1194361400.851894.46660@y42g2000hsy.googlegroups.com...> On Nov 6, 6:20 am, "blisca" <bliscachiocciolinatiscali.it> wrote: > > Hi ,i like to use cpld and fpgas scraped by boards at home at thepurpose of> > practicing VHDL. > > I have some Spartan 3 XC3S1500,and an inexpensive Digilent JTAG cable > > rated 1.8 to 5.5 V. > > There is some trick to use it for programming a Spartan 3 ,having a core > > voltage of 1,2V? > > Thanks > > Diego,Italy > > > The programming cable does not interface to the core voltage of the > FPGA, only the I/O voltage for the JTAG. In some parts this is a > separate JTAG or Auxiliary supply voltage. On other parts it may > be Vcco for a particular bank. Usually it is in the range of 1.8 > to 3.3V so there is no issue with the Digilent cable in this regard. > > I'm not familiar with the Digilent cable, but the Xilinx parallel > cables have a pin for the interface voltage usually labelled Vcc > that must be connected to the I/O voltage of the devices to be > programmed. > > HTH, > GaborMany thanks,maybe i was misleaded by the fact that 1,8 V looks like a core voltage