Help controlling a capstan motor salvaged from a panasonic VCR

[carlynorama]

Hi there,

I am trying to appropriate the motors out of an old vcr.

I have a VEM0800 motor attached to a board with a BA6868FM chip on it.

The board is labeled VEP02579A, other markings on the motor include "EP23AA" and "403201"

This is the only data sheet I have for the chip is:
http://media.digikey.com/pdf/Data%20Sheets/Rohm%20PDFs/BA6868FM.pdf

Before I spend too much more time on this I was wondering if anyone knows where I can get a pinout for the 8 pin header on the board?

The assembly was given to me already removed from the vcr so I can't trace it back that way. If no one knows I'll go through checking continuity pin by pin, but I'm trying to avoid that.

Thanks,
-c

[jurb...@gmail.com]

?Nothing solid yet, but I would recommend getting a print for one of the VCRs that use this motor.

ther eis one here : https://www.partstore.com/CompatibleModels.aspx?MfgName=Matsushita&BrandName=Panasonic&PartNumber=VEM0800&ItemCondition=New&page=3

VCRs control these motors quite well and reverse them and all that so getting the print for any of the VCRs tyhat use that motor should give you the methoid of how to control it.

You could do it yourself from scratch if you want to reinvent the wheel, but do you ?

If so and you got good reason, say so. you could concievabvly connect to the motor board and discard their inadequate chip. But why ? I know they had a way to report the phase back to the servo chip but never looked into it. they did this for slow tracking. Rmeember slow trackng ?

Anyway, get the print for any of those machines and you should be able to do what you want to do. If not, say so...

[carlynorama]

Thank you for the info. That list is very helpful and I could take it with me to a thrift store to look for one of those model, for sure. I'm unfamiliar with the term "the print" - is that another way to refer to the main printed circuit board?

I'll keep you all posted.

[carlynorama]

I sounded out the pins:
http://www.flickr.com/photos/carlynorama/10825176416/

S1 H4, IC20 (VCC)
S2 IC18, 19 (N.C. VM)
S3 H3
S4 H2
S5 IC9 (TL)
S6 IC10 (EC)
S7 IC 11 (ED/S)
S8 IC 2, 3, 8, 12, 13
(SGND, N.C., MGND,
CS,RNF)

With my notes on the pins:
1, PCV -
2, SGND - signal GND
3, N.C. - Not Connected
4, OSC - Oscillation
5, RCC - Ripple cancel
6, ECR - Output voltage control reference pin (between 2.0 and 2.4)
7, CNF - Capacitor connection pin for phase compensation
8, MGND - Motor GND
9, TL - Torque limit
10, EC - Output voltage control pin
11, ED/S - Rotation Direction Current detecting input terminal F: upto 2.2V, R: more than 2.8
12, CS - Current detecting input terminal
13, RNF - Resistance connection pin for output current detection. Torque limit and I/O gain settings are made by the RNF resistance value
14, N.C. - Not Connected
15, A1 - coil output
16, A2 - coil output
17, A3 - coil output
18, N.C. - Not Connected
19, VM - Motor power supply pin
20, Vcc - Power supply pin
21, VH+ - Hall Power supply (in or out?, maybe Hall bias input pin)(between 2.45 and 2.85)
22, H3- - Hall signal input pin
23, H3+ - Hall signal input pin
24, H1- - Hall signal input pin
25, H1+ - Hall signal input pin
26, H2- - Hall signal input pin
27, H2+ - Hall signal input pin
28, PCI -

similar chip: http://rohmfs.rohm.com/en/products/databook/datasheet/ic/motor/odd/ba6859afp-y-e.pdf

I don't 100% get what they all do, but I can power it up now and experiment.

I'll let you know if I get it working.