I recently dusted off my old Pic test board (a Brinck br873) which, as far as I can tell from the schematics, is a ludipipo style programmer.
I used to program it using IC-prog and choosing the JDM programmer setting. However, after having tried several programs(ponyprog, prog84, two flavours of winpic, ntpicprog, pip02, icprog ver. 1.05, 1.05D and
1.04) in both windows xp, linux and win98, the only thing that's worked for me is the old Pix program in a dosbox in '98.
The other programmers try to program the chip (the LEDs on the board do their thing), but the programming fails, and the programmers can't read the chip.
This poses a problem because I'd like to use a 16C717 for my current project instead of the 16F84A that I've tested with - and Pix simply doesn't know that chip.
So, does anybody here have any advice that doesn't involve getting a new programmer? :-)
Were all of these on the same machine? ludipipo is a serial programmer and utilizes the voltages of the RS232 port to accmplish programming. Many modern serial ports no longer produce the voltages to drive the programming process properly.
Which chip?
So you tested with the 16F84A. That's probably a voltage problem.
You want to program a 16C717 OTP. Simply put, it won't work. If you check out the programming specifications for the 16C717 you will find that it requires 50 ma of current for Vpp. No serial port in the universe is going to put out that much current. At the very minimum you'll need an external Vpp circuit to supply the proper voltage/current.
You'll need to take care in scouting out a programmer. Most PIC programmers nowadays are designed to program flash parts, which have a minimal voltage and current rating for Vpp. EPROM based parts, such as the 16C717 need proper voltage and current (13V @ 50ma) in order to program the EPROM cells.
Nope. You'll need programmer that can supply the proper Vpp voltage and current.
I decided to test out pyascii. You can find it here:
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View with a fixed font. This circuit will provide up to 130 ma of current at
13V to Vpp controlled by a low voltage signal Vppin. The LM317 regulator is configured as a digital switch offering 13V@130mA to Vpp when Vppin is low and grounding Vpp when Vpp is high. Q2 will ground the ADJ pin of the LM317 making the output voltage 1.25V@12.5mA. Q1 shunts that current to ground. When Q1 and Q2 are off then R2 and R3 sets th voltage to 13V. Good values for R2 and R3 would be 2.2K and 240 ohms respectively.
You could use this circuit to enhance my Trivial LVP programmer found here
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The 2N2222 that's already in the circuit is Q1 below. You can replace the
1K between the 13V and MCLR with the 100 ohm R1. Then extend the 13V input with the rest of the circuit below.
+---------------------------+ | | | LM317 | 100 | | R1 16V --------|IN OUT|-------------/\/\--------------+---- Vpp | | | | ADJ | | +---------------------------+ | | \| | |-----+ | /| Q1 | | | | \R2 | | / | | \ | | | | | +----------------+ | | | | | | \R3 | | | / | | | 500 \ \| | | R4 | |---------------------------------+--/\/\---Vppin | /| Q2 | | | | +----------------+---------------------------+ | | | Gnd
I figured that as well - the linux and winxp stuff was done on my athlon xp workstation. I actually had to find a serial port in my electronic junk heap because it was only implemented as a connector on the motherboard....
However, I used my old 133MHz laptop for the win98/dos part - and I'm still curious as to how it can be that I can't use icprog on that computer since Pix works fine - that suggests to me that the electrical part is good. Oh well....
For all my test cases I used a 16F84A. Pix actually only does 16C84, but the match seems to be close enough that it doesn't matter...
Yeah, I'm somewhat convinced that my programmer operates with questionable voltage levels...that may just be me.
Argh, I had assumed the 16C717 was EEPROM based - Oh well, I suppose I'd better switch to the 16F88 then - in principle I suppose that would enable me to use my old programmer.
Thanks for the heads-up. Although I've known about the PIC MCUs for years, I never realized that the main difference between the C and the F units was that F is EEPROM. Simply amazing. I think I'll stay away from OTP parts since I mostly use PICs for tinkering.
Anyway, I've decided that I'd be better off with a DIY USB programmer (I'm thinking the K150) - then I'd be able to program from my powerbook which has no serial port :)=
(oh, and I was about to post an ASCII schematic of my old programmer, made in my Favorite Editor(tm)(because pyascii behaved a little weird when I tried it), but I thought I'd spare you the gory details ;))
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