Re: [Usbpicprog-technical] new PCB and current software status

[Frans S. <fra...@gm...>]

Hi Francesco,

I have just married, so in the last couple of weeks I had some other 
things to do :)
I have already changed the circuitry of the voltage pump, but I am 
afraid that a voltage divider would unnecessarily take current from the 
voltage pump. By the way, I have not released the 0.3 yet, because it 
needs some additional changes in the values of some resistors and some 
last checkups.

I will check the latest software tomorrow!

Cheers,

Frans

Francesco Montorsi wrote:
> Hi Frans,
>     I've noticed that you have committed a new version of the PCB (rev 0.3); it 
> seems the new schematic will allow to support also lower-voltage PICs; I'll try 
> to test it asap (if you say it's ready to be "beta-tested").
>
> May I suggest a new feature? When building UPP for the first time I found out 
> that most of the times the UPP failures were due to the pump not reaching 12V 
> for some reason. I see that pin #12 (AN11) of the PIC18F2550 used in the 
> programmer is not connected to anything.
> Connecting it to VPP (through a voltage divider) would allow the firmware to 
> self-test the charge-pump using its internal ADC.
>
> I understand that this would further complicate the routing but if it turns out 
> that this is not a big problem, then I think the two additional resistors are 
> worth it :)
>
> -----
>
> Other question: does current software/firmware works for you?
> I have revised almost all code of upp_wx, in particular the Hardware class, with 
> the aim of reducing redundancy and add more safety checks... this helped me to 
> better understand the internals of UPP but I still cannot currently 
> program&verify any of the following devices I have tested:
> - 16F84A
> - 18F2550
> - 18F4450
> I don't know if the problem lies
> a) in my UPP HW
> b) in the cable a little bit too long I'm using to connect UPP with PICs under 
> tests (unfortunately I cannot easily cut it)
> c) in the read or program operations of the firmware
>
> OTOH if I do a "program without verify" cycle UPP says everything was programmed 
> fine (except for the 16F84A which says "verify error during programming"); I'll 
> soon test if this is the case (putting the PIC in the real circuit where it 
> needs to go).
>
> I'm using firmware rev 547....
>
> I don't think the problem is the software since in my cases it fails just 
> because of the (error) codes returned by the firmware but just to be sure: does 
> current software works for you?
>
>
> Bye,
> Francesco
>
>
>