EasyProg PIC Programmer Kit Assembly Hints
Last Updated 20 November 2005
This page provides some guidance if you are building an EasyProg from an
official kit or from parts collected on your own. It is assumed you
are building up an official bare board. If you're trying to build
one completely from scratch then you're really on your own,
although some of the comments below might still be useful.
Extra capacitor in the kit
Some kits contain a 1uF 50V electrolytic capacitor. No such
capacitor is called for in the bill of materials. If you have one
of these left over after you think everything is installed, you're right,
there is no place to put it. Consider it a bonus freebie.
Bend resistor leads tightly
The board uses .3 inch spacing between leads of the 1/4 watt resistors and
other parts. This spacing is tighter than used for the same parts
on some other boards. To get the leads to fit easily into the holes,
bend the leads down by hand right at the resistor body.
Finding parts on the board and schematic
Most parts are well marked on the board, but in a few cases the part
designator is accidentally overlapping a via making the designator hard to
read. Two files are provided for finding parts easily.
We recommend you print out the board drawing and use
that to find parts visually instead of the board. This will be
bigger, writing won't be covered up as parts are installed, and some of
the part designators were moved away from vias.
In addition, the parts locator index is useful
for deliberatly finding parts. This file gives the schematic
location and board location for each part. The board coordinates
are in inches, which is the same units the board drawing is marked
with. The schematic location is shown as a page number, and a
coordinate that is always a letter and a single digit. This
coordinate refers to the letters and digits in the frame around each
schematic sheet. Take a look at the schematic and this should be
Assembly and test order
We recommend the sequence below for building and testing an EasyProg
kit. This sequence is designed to minimize damage if assembly
errors are made. Proceed thru these steps sequentially. Do
not proceed to subsequent steps until the current step is completed and
verified as applicable. Ignoring a fault condition won't make it go
away, and can cause permanent damage in subsequent steps.
The directions here are only general guidelines and hints. You are
expected to be able to read and understand the schematic and diagnose
problems on your own. Nothing on this web page should be considered
a substitute for using your own brain. In the end it's your
responsibility alone to get the kit working.
Voltages are with respect to ground unless explicitly stated
otherwise. The shield of the RS-232 connector is connected to
ground, and is probably the easiest place to attach the ground clip of a
meter or scope probe.
Install most parts
Install all the parts except IC1 (LM324 opamp), IC2 (PIC 16F648A), and IC3
(ST232 or equivalent). Install the socket for IC2 but do not insert
Double check the polarity of the two electrolytic capacitors, C16 and
C18. The positive leads should be towards the front of the board, as
indicated by the "+" marks closest to these leads just outside the
footprint of the capacitors. Electrolytic capacitor markings vary,
and may only be marked on the minus side, which should be towards the back
of the board.
Check unregulated supply
Power up the unit and check the unregulated supply voltage. This
can be done by measuring the voltage between the cathode (banded end) of
D4 or D5 and ground. D4 and D5 are near the far left corner of the
board. If using the supplied wall wart with US power, this should
be about 25V. Regardless of the power source, this must be from 17
to 30 volts or the unit will not work correctly and can possibly be
damaged. If you don't get the expected voltage, go to page 5 of the
schematic and troubleshoot. As you can see from the schematic,
there is very little between the power input and the unregulated
supply. One or more diodes may be installed backwards.
Check 5V supply
Check the voltage at pin 14 of the socket at IC2. This should be 5
volts within a few percent. If not, see schematic page 5.
The 5 volt regulator IC4 may be installed incorrectly.
Disconnect the input power.
Install IC1, IC3.
With the power off, install IC1 and IC3.
Check RS-232 charge pump
Turn on the power and check the voltage on pin 6 of IC3. This
should be around -8 volts, and certainly within the range of -6 to -10
volts. If so, proceed to the next step. If not see schematic
Pin 2 of IC3 should be about 9 volts. If so, the positive charge
pump is working but not the negative charge pump, which starts with the
voltage produced by the positive charge pump at pin 2. Suspect C13,
C14, and pins 4, 5, and 6 of IC3.
If pin 2 is not around 9V, then the positive charge pump is broken.
Suspect the power connections to IC3, C11, C12, and their connections to
Check main controller
Disconnect power. Plug IC2 into its socket noting the
orientation. Turn on power. If the LED lights dimly, proceed
to the next step.
If the LED does not light, then the main controller is not working.
Unfortunately a lot of things can cause this. See page 3 of the
schematic. Verify that pin 5 is at ground and that pin 14 is at 5
volts. Check that the oscillator is running. There should be
a 20MHz signal on pin 15, although this must be measured with a high
impedence like a 10x scope probe. Normal 1x scope probes can load
the line so that the oscillator does not run even when it otherwise
Connect the supplied serial cable to a standard COM port on the PC.
We will assume you have connected the cable to COM 1. If not, then
add the command line option "-sio x" where "x" is the COM port number to
the command lines listed below.
Go to a command prompt window and enter the command:
If everything is working, you should get a message indicating that the
firmware type is EasyProg and giving the version. It will also
complain that it was unable to read the device ID of the target chip,
blah, blah, blah. This is normal when the EasyProg is not connected
to a target circuit and nothing is in the ZIF socket.
Check programming voltages
If you're feeling lucky, impatient, or think you've done everything right,
you can skip this step and get back to it if you have a problem with the
Enter the command:
pic_ctrl -vdd 5
and measure the voltage at the Vdd pad at the right edge of the board just
in front of the RJ-12 connector. The LED will start flashing and
the voltage should be 5 volts. Depending on firmware version, this
may only last about 5 seconds and the LED will stop flashing and the
voltage will go back to 0 volts. Try a few other values in the
range of 0 to 6 to the -VDD command line option. The voltage should
go to the specified value, at least for about 5 seconds.
Now enter the command:
pic_ctrl -vpp 13
and measure the voltage on the Vpp pad next to the Vdd pad. It
should be about 13 volts. Just like Vdd, this may only last 5
seconds. Only values of 13 and 0 are legal on the -VPP command line
option when using an EasyProg.
to make sure that the programmer is in its normal quiescient state before
proceeding to the next step.
Try PIC in ZIF socket
Put the DIP version of any of the PICs listed as supported on the EasyProg
web page in the ZIF socket. Note that not all
PICs are supported in the ZIF socket even though they are supported for
in-circuit programming. Make sure pin 1 of the PIC is inserted in
PIN 1 (near left corner) of the ZIF socket.
It should identify the PIC and its silicon revision, in addition to the
programmer firmware type as "EasyProg" and its version, and the elapsed
time for the operation.
Read the User's guide
The User's Guide explains the normal
operation of the EasyProg, the meaning of the LED blink patterns, how to
upgrade firmware, and a bunch of other things.
Read ICSP overview
Before trying to use the the EasyProg to program a PIC in circuit, we
recommend you read the ICSP Overview.