Pavel, thanks! Note, I was working from the Lattice data book and the commercial cable that I use from the ISP Starter Kit that I bought around three years ago. I noticed a discrepancy between the two and generated the schematic based on my cable as well as the prototype programming board that I use. I have never had any problems programming ispLSI1016s, 2032s, and GAL22V10s. Given the noise immunity of the 74HC family I'm curious as to why they would go back to the 74LS part. I can only speculate that they had drive problems relating to driving several daisy-chained devices or the newer 1016E. I'll update my schematic to provide 1K pullups instead of 10K but I should give Lattice a call to see why they changed the 74xx367. The other updates are already included in my schematic. - Tom At 05:20 PM 7/8/98 +0200, Pavel Korensky wrote: >At 06:18 8.7.1998 -0700, Tom Handley wrote: >> Mercy, I've added a schematic for a buffered parallel port cable and >>programming board that allows you to program Lattice Semiconductor's >>ispLSI1016, ispLSI2032, and ispGAL22V10 devices. This is for folks that >>don't have Lattice's ISP Starter Kit. You can download the archive from my >>web page at: >> >> http://www.teleport.com/~thandley/Wilbure.htm >> >> To program their ispGAL22V10 all you need is the buffered cable which >>basically contains a 74HC367 and some passive components, and the ISP Daisy >>Chain Download software which is also on Lattice's web site. >> > >Tom, > >in your picture of the cable schematic is a small error. The cable >schematic is the same as is in the 1994 Lattice Data Book. >But it is not the same what actually is in the commercial ispDOWNLOAD cable. >There was a thread in USENET sometime ago (I found it at www.dejanews.com) >and someone from Lattice company posted the actual schematic of the cable. >It seems that they had some problem with the cable built around the 74HC367 >chip, so they decided to remove schematic from actual databook and from Web >page. > >Best regards > >PavelK > > > > >P.S. Here is the above mentioned message. > > >======================================================================== >START OF EMBEDDED MESSAGE > > accordingly. Summary: Added 560 pF caps to ground and 100 ohm series > resistors between buffer and device. Changed pullups to 1K. Added 1K > pulldown to LPT pin 15 (Vcc detect). Changed CMOS buffer to LSTTL. > > Maybe when they discovered their serial connection was subject to noise, > they were too embarrassed to admit that peoples' troubles were caused by > the faulty specification and not because of poor construction. So they > quietly upgraded their own cables and deleted the bad drawing from the > databook without providing the improved schematic. > > -------------------------------------------------------------------------- > > Lattice isp Cable per p. 2-10, 1994 Lattice isp Manual > and per p. 2-50, 1994 Lattice Data Book > modified per an actual cable provided in the $99 Synario ISP kit. > ------------------------------------------------ > > DB25 Parallel Port isp Interface > ------------------ ------------- > > DY-b Pin nn Label isp > Y = I Input Base+1:I/O Status Adr. > Y = O Output Base+0:I/O Data Adr. > b = bit (0 to 7) of I/O Byte > nn = DB25S Pin Number > > 74LS367 > > Vpwr > _|_______ > | /| | > DI-6 Pin 10 -------------------< |-----------SDOUT > | o\| | > | | | > +-------+ | > | | | | > | | |\o | 100 > DO-0 Pin 2 -------------)-----| >------------*---/\/\/\/---SDIN > | | |/ | | > +-------+ | +-||--GND > | | | | 560pF > | | |\o | 100 > DO-1 Pin 3 -------------)-----| >------------*---/\/\/\/---SCLK > | | |/ | | > +-------+ | +-||--GND > | | | | 560pF > | | |\o | 100 > DO-2 Pin 4 -------------)-----| >------------*---/\/\/\/---MODE > Vpwr | | |/ | | > | | | +---------+ +-||--GND > 1K | | | | | 560pF > | | | |\o | | 100 _____ > DO-3 Pin 5 ------+------+-----| >--------)---*---/\/\/\/---ispEN > Vpwr | |/ | | | > | | +---------+ +-||--GND > 1K | | | _|_ 560pF > | | |\o | - > DO-4 Pin 6 ------+------------| >------------no connect > | |/ | > |_________| > | > GND > DO-6 Pin 8 ------------+ > | Port Sense > DI-5 Pin 12 -----------+ > > Vpwr O Vcc > | | /| | > DI-3 Pin 15 ---/\/\/\/----*-------*-----*----|< |-------+ > 220 | | | \| > < ----- > 1K < ----- .1uF > | | > GND Pin 20 --------------*-------*---------------------+ > _|_ > - > > -------------------------------------------------------------------------- >| >| RJ-45 8-pin cable onto isp Starter Kit >| >| Looking into each: ________ >| ________ contacts-->|87654321| >| |12345678|<--contacts | | >| |________| MALE FEMALE |__ __| >| (__) <---little lever |__|__|__| >| _____ >| 1 - SCLK 5 - ispEN >| 2 - GND 6 - SDI >| 3 - MODE 7 - SDO >| 4 - no connect 8 - Vcc >| >| | .100" header >| | ------------ >| | 1 Vcc >| | 2 SDO >| | 3 SDI >| | 4 /ispEN >| | 5 no connect (plugged, yet wired to buffer output) >| | 6 MODE >| | 7 GROUND >| | 8 SCLK > >----------------------------------------------------------------- > > >============================================================================ >END OF EMBEDDED MESSAGE > > >************************************************************************** >* Pavel Korensky * >* DATOR3 LAN Services spol. s r.o. * >* Modranska 1895/17, 143 00, Prague 4, Czech Republic * >* * >* PGP Key fingerprint: F3 E1 AE BC 34 18 CB A6 CC D0 DA 9E 79 03 41 D4 * >* * >* SUMMA SCIENTIA - NIHIL SCIRE * >************************************************************************** > >