Inchworm components

[gregmcc]

I've just received my inchworm kit and its almost completed but have a question on some of the component values. In the pdf file the capacitors listed are:


1 C1 0.33uF 25V
2 C2,9 47uF 25V
3 C3,4,5 0.1uF
5 C6,7,8,11,12 10uF 16V
2 C10,13 33pF

In my kit I received:

5 x 2.2uF Elec
2 x 22pF
4 x 0.1uF
1 x 47uF Elec
1 x 22uF Elec

Are the values in the pdf not critical, or did i get the wrong values.
What would the new values be:
C1 = 0.1u, C6=2.2u, C2=47u, C3=0.1u, C10=22p?

I hope this is the right place to post this as I cannot find a support forum inchworm.

 

[William At MyBlueRoom]

Well aside from mailing me directly you found the right place. Many parts are non critical and DIPMicro adds their own (He buys in bulk)

The 2.2uf are fine, anything from 2.2uf to 10uf will work on the ST232

C1 is optional, the LM7805 suggests 0.33 but 0.1 works fine.
22pf is fine for C10 & 13

C9 = 22uf
C6,7,8,11,12 = 2.2uf
C2 = 47uf

Have fun with the kit.

 

[gregmcc]

Excellent - thanks. Should have it finished in a jiffy. Then the fun begins!

 

[William At MyBlueRoom]

Download the Inchworm quick project PDF from my site.

 

[gregmcc]

Already it got it Gonna be the first thing I try.

 

[gregmcc]

I'm having a few problems

Inchworm is built and I've connected it up and setup mplab - disabled fifo, using a 1:1 serial cable. When connecting in mplab I get the following:

Connecting to MPLAB ICD 2
...Connected
ICDWarn0054: MPLAB IDE has lost communications with the MPLAB ICD 2. Would you like to attempt to reconnect?
Connecting to MPLAB ICD 2
...Connected
ICD0286: Unable to communicate with ICD
ICD0082: Failed MPLAB ICD 2 operation
MPLAB ICD 2 Ready

If I try and run the self test in status the same error occurs as above. I've read a few posts with similiar problems - already checked the cable. Also viewing the power in mplab shows 0.00
If I try and do a download OS I get:

Downloading Operating System
ICD0152: Failed to read all of requested bytes (0x0 of 0x8)
...Download Operating System Failed
ICD0152: Failed to read all of requested bytes (0x0 of 0x2)
ICD0082: Failed MPLAB ICD 2 operation
ICD0082: Failed MPLAB ICD 2 operation
ICD0082: Failed MPLAB ICD 2 operation
ICD0082: Failed MPLAB ICD 2 operation
MPLAB ICD 2 Ready


I've not yet connected any pics up to the inchworm.

Update: I've also checked the 5V and TP VPP=13.36V

 

[William At MyBlueRoom]

what COM port (only 1 and 2 work)
Are you using a USB - RS232 cable? What OS are you running? Which MPLAB are you running?

 

[gregmcc]

XP SP2, Com1, RS232 Cable.
MPlab 7.50

I've also restarted after I disabled the fifo

 

[Sig239]

Same thing here(as original poster). Dipmicro supplied a 10V cap instead of a 25V cap for C2. I don't really feel good about the derating so I'm going to put my own 68uF 35V cap in. I guess since it is just to reduce ripple on a 5V line the one it came with will be fine, but I would like it at least as good as the original design (the way it was tested). I will put the same thing in for C9.

Also one of the plated through holes on P1 did not turn out right.

Overall I am still very happy. You can't beat 36$ for this level of programmer. Customer service with Dipmicro is great and the components are high quality. Except for the one minor flaw, the board looks fantastic.

Silly me forgot to order any microcontrollers, so assembly and testing to come later.

 

[William At MyBlueRoom]

I'm going to supply parts myself for the next batch of Inchworms. I don't mind a couple of part subs for non critical parts but drilling out holes is not something I can reccomend, DIPMicro has modded the PCB that's why the plated hole sticks up. Your wire should solve it nicely but it is something I'll fix (larger holes for P1) so we can use more commonly available power connectors.

The larger caps will be fine, you don't need C9 to be too large but it has to be rated for > 16V. It won't affect the OS loading or give you connection problems. It's strickly for the VPP supply.

Well I've taken a brand new Inchworm and will capture the steps. Are you using your own 16F877A or 16F877? Or is it the one supplied from DIPMicro?

Connecting to MPLAB ICD 2
ICD0019: Communications: Failed to open port: (Windows::GetLastError() = 0x2, 'The system cannot find the file specified.
')
ICD0021: Unable to connect with MPLAB ICD 2

Now choose under settings COM1 or COM2

MPLAB ICD 2 Ready
ICDWarn0034: Please ensure that your system's serial FIFO buffers are disabled.
Connecting to MPLAB ICD 2
ICD0082: Failed MPLAB ICD 2 operation
ICD0021: Unable to connect with MPLAB ICD 2
MPLAB ICD 2 Ready

Here is where you must download an OS The file is
ICD01020701.HEX

Downloading Operating System
Connecting to MPLAB ICD 2
...Connected
Setting Vdd source to MPLAB ICD 2
ICDWarn0020: Invalid target device id (expected=0x71, read=0x0)

(Normal till you have a target PIC attached, a sign its working actually)

...Reading ICD Product ID
Running ICD Self Test
...Passed
...Download Operating System Succeeded
MPLAB ICD 2 Ready

That all there is.
Make sure all the diodes are in the right way. Also make sure you have at least a 7.5V or greater 300ma power supply connected. (Yes someone tried it without a powersuppy thinking it was like a JDM type programmer)

Now if I have a blank or not present 16F877A the MPLAB looks like this...
Connecting to MPLAB ICD 2
ICD0019: Communications: Failed to open port: (Windows::GetLastError() = 0x2, 'The system cannot find the file specified.
')
ICD0021: Unable to connect with MPLAB ICD 2
MPLAB ICD 2 Ready
ICDWarn0034: Please ensure that your system's serial FIFO buffers are disabled.
Connecting to MPLAB ICD 2
ICDWarn0054: MPLAB IDE has lost communications with the MPLAB ICD 2. Would you like to attempt to reconnect?
Connecting to MPLAB ICD 2
ICD0021: Unable to connect with MPLAB ICD 2
MPLAB ICD 2 Ready
Downloading Operating System
ICD0021: Unable to connect with MPLAB ICD 2
...Download Operating System Failed
ICD0286: Unable to communicate with ICD
ICD0286: Unable to communicate with ICD
ICD0286: Unable to communicate with ICD
ICD0286: Unable to communicate with ICD
ICD0286: Unable to communicate with ICD
MPLAB ICD 2 Ready

 

[gregmcc]

Thanks for the info - I'll go through all the components and triple check everything. I'll also connect up a 16f628a pic and see what happens.

Also a suggestion for us noobs It is possible to make the busy led flash on startup - that way we (I) at least know that uC is working. You could also use this for version control - 2 short flashes for version 0.1 of the code, a short and a long flash for version 0.2 etc etc - just an idea.

I'll let you know on my findings.

My P1 pad also looks like the pic above - but its not causing any problems. I have to agree, excellent quality PCB, now to just get it working

 

[Nigel Goodwin]

Also a suggestion for us noobs It is possible to make the busy led flash on startup - that way we (I) at least know that uC is working. You could also use this for version control - 2 short flashes for version 0.1 of the code, a short and a long flash for version 0.2 etc etc - just an idea.

The Inchworm is an ICD2 clone, so it uses the software provided by MicroChip as part of MPLAB - Bill hasn't written any software for it.

 

[gregmcc]

I mean the firmware for the PIC on the inchworm (the 16F877A which runs ICD2_BOOTLOADER_A.HEX)

Update: After re-reading the post I thought you were refering to the MPLab software, you mean the the hex is provided by microchip as well?

 

[Nigel Goodwin]

I mean the firmware for the PIC on the inchworm (the 16F877A which runs ICD2_BOOTLOADER_A.HEX)

See my previous reply!.

 

[gregmcc]

Thanks - see my update

I'm a little slow this morning - too many late nights filddeling with PICs

 

[Sig239]

Well it appears that some of the 1% resistors I recieved with the kit are also out of spec The 6.8k resistors are reading low 6490hm:, 6710hm: and the 2.2k are reading high 2235hm:,2242hm:. Will these be too far off for the voltage dividers? I checked a bunch of other 1% resistors that I have (none the right value of course) and they were all well within spec. I check resistors from 47 hm: (47.2) all the way to 10Khm: (9.98k). Response is appreciated.

 

[William At MyBlueRoom]

Well it appears that some of the 1% resistors I recieved with the kit are also out of spec The 6.8k resistors are reading low 6490hm:, 6710hm: and the 2.2k are reading high 2235hm:,2242hm:. Will these be too far off for the voltage dividers? I checked a bunch of other 1% resistors that I have (none the right value of course) and they were all well within spec. I check resistors from 47 hm: (47.2) all the way to 10Khm: (9.98k). Response is appreciated.

There is a wide range of VPP that will function, all those values will be fine.

 

[Sig239]

Thanks, that's what I wanted to see. I have it all soldered up. Now I just have to find a proper wall wart (I know I have one here somewhere) so I can check the 5V supply then install the ICs and check the other voltages. I still don't have a :mu:controller to test yet.

 

[William At MyBlueRoom]

You can still test the Inchworm, Download the OS and then you'll be able to check your voltage levels from within MPLAB (status screen)

 

[gregmcc]

I'm still seem to be having problems. I've checked all the resistors with a meter, checked diodes and polarity, checked caps - all good. Also beep'ed out the rs232 cable - no problems there. I bought the kit through dipmicro so i presume its programmed.

try as I might I can't get it to work. Sig239 - yours working yet?