[hpsdr] Terasic USB Byte Blaster - Problem resolved

[Graham / KE9H]

To all who have Terasic USB Blasters:

There was a problem reported programming the
PROM on Mercury using a Terasic USB Blaster.

Thanks to Scotty for figuring out this problem.

It turns out that Mercury was built with a wrong
value resistor in a PROM programming line.

R10 should have been 22 Ohms, but was built with
220 Ohms.  You should either replace R10 with the
correct value of 22 Ohms, or jumper it with wire
( 0 Ohms ).  Either will work fine.

Although Altera Byte Blasters seem to be able to
program the PROM with the 220 Ohm resistor in place,
it is likely on the edge, and you may want to make
this change, also.

This has no effect on normal operation of Mercury, and
has no effect on the ability to program Mercury
via Ozy.  It is only an issue when programming
the PROM through the 2x5 PROM connector J4.

--- Graham

==

Graham / KE9H wrote:
 > All:
 >
 > There are a number of you on this list, myself included, that
 > have purchased a Terasic USB Blaster as a way to change the
 > code on the HPSDR cards, as an alternative to the much higher
 > priced Altera USB Byte Blaster.
 >
 > I have been unable to update the PROM on my
 > Mercury card with my new Terasic USB-Blaster.
 >
 > Bill T. reported that he could program his Mercury PROM.
 >
 > So, I just spent the morning up at Bill's house trying to debug
 > what was happening.
 >
 > It turns out that both my and his Terasic Byte Blaster will
 > program the PROM on an Alpha-2 (prototype) version of Mercury.
 > Neither will program the PROM on a production Mercury.
 >
 > An Altera Byte Blaster will program the PROM on both versions
 > of Mercury.
 >
 > The is not supposed to be a difference between the programmers,
 > and there is not supposed to be a difference on the PROM
 > programming port on Mercury.  But "no difference" is apparently
 > a relative term.
 >
 > Scotty has agreed to dig into this issue.  We will let you know
 > what the conclusion might be.
 >
 > Those of you who have not yet purchased a Byte Blaster should
 > not be concerned.  There is an alternate method coming soon,
 > where Ozy is downloaded with Byte Blaster code, and then can
 > program the PROMs or FPGAs on the HPSDR cards via the
 > Atlas bus JTAG link.  This method is in Alpha test at this time,
 > and is working.
 >
 > --- Graham / KE9H
 >
 > ==
 >
 >