This might sound stupid but I've been racking my brains and I can't figure out if what I want is possible
I have a pwm output from a controller that controls a laser power supply. Currently 100% on the controller gives 30ma current on the supply 10% gives 5ma current
There is no way to adjust the levels on either the controller or psu to do what I want.
I want to change the pwm So that 1% duty is boosted to 10%. So that in effect 1% will output 10ma on psu
So instead of the pwm going from 0v to 5v it goes from 1v to 5v?
i havent got that far yet ian. i am just getting my head around logic analysers. when i run a capture if i probe +3.3 or gnd then all is good as shown in chans 2 - 4 above but when i probe the circuit all i get is the form above. if i increase / decrease sample rate then the the form gets longer or shorter but never the less the same.
heres what im doing please let me know if im right/wrong. i probe the gnd in the circuit with the gnd of the BP then probe the other io/points on the reader with the miso,cs,mosi,clk and aux
all i get is the same form as above
is it possibly that this is mains / noise interferece, if so can i get rid of it?
Hi guys finally got hands on a meter. but have a problem.
i cannot find the gnd point for the reader. as this is mains powered its opto isolated from the main board and i cant figure out how to workour which pin is gnd and whats not.
when i metered the pins they all seem to have different values and i cannot find a common pin i can call gnd.
am i being dull and mising something obvious? ok i think i found the gnd.
im trying to work out how to use the bp as a logic sniffer. i have it working sort of, but i keep getting the same results every time. with probes connected or not.
ok from a quick read of the BP as an logic sniffer i see its not very fast, and the OLS is idealy what i need, but for now ill have a look and try it out with the BP and see what i get.
dont have an OLS atm its still on the wish list :(
i have a meter being droped over later so i can have a look. il post back with more info when i get it, i noticed there was a post about using the BusPirate as a logic sniffer going to find it again and have a read, will it be fast enough do you think? or am i definitly going to need the OLS?
yes ian i beleive most places will have a similar system,
its a technically a model to take advantage of people who cannot afford to pay lots of money or who have bad credit,
its a good plan but i just dont think its fair they increase the initial value of the item before they add interest, they end up making 200% profit above normal retail, £500 tv from shop will cost you £750 to buy cash from that company, then they add there interest and you end up paying back a total of £1500, thats exploitation im my eyes.
it all started as a way to let the unemployed/low income/bad credit family's have nice things and make money from people who cant really afford it,
you have a new tv and stick cash in a meter to watch it, even the lowest income familys could find a few ££ a week to put in the meter even if they couldnt really afford it. ive even heard of people missing meals / living on scraps for a few days to "feed the meter" as they call it,
Yes ian they can be quite expensive, around the £600 mark for the larger lcd's, its not so much the price thats the reason for the meters its giving people credit without a credit check.
basically if you have a bad credit rating, you cant cet credit from the large electronic stores. but these smaller companys offer the same tv/hifi/pc stuff, but the interest is higher and the products are more expensive to start with, say they charge you £900 for a £600 tv, then the interest on top takes it to £1200, but some people have no chioce and cannot get normal credit or cant afford to pay out £600 in one go
so instead of having collectors go door to door for the money they setup the PPV system. it used to be using £1 coins and some still do, and you get say 1hr(time) of power to the tv for £1, but that means a collector has to colect the money, so now they are swicthing to keys/tokens as no colectors are needed so making them even more money.
@tempmj
yes you topup the dongle like you do a mobile phone they use a comapny here called paypoint which deals with all kinds of payments, gas, elec, mobiles, tv licence,court fines, creditcard bills, you name it you can pay for it using the paypoint service, so they use this same service, you goto a shop that has paypoint and tell the person £10 on here please and hand them the money and token/key/card and they add the cash to it, i pay my speeding fines using the same system, but using a mag swipe card instead,
so your not going to there company office to pay, but its still paid to them directly if you get me.
the reason is this, some people will agree to pay say £20 a week payment for the tv, so they install the tv, they set the meter to make sure it uses at least £20 a week to watch the tv. to actually watch that tv the person has to have credit in the meter, no credit no tv, so you have no choice but to buy credit and therefore pay your bill. without the meter system people may spend the money that should have gone to pay tv, and end up behind in payment and have the tv taken off them,
so basically its a system to make sure you pay, no credit no tv, if for example the weather is lovley as it was here a few weeks ago, no one is in watching tv they are all down beach, so that week they only watch 2hrs of tv. they still owe £18 to the comapny for that week so still have to pay it and still owe £20 for the next week.
there is no tracking of channels afaik its simply a device that turn on and off electricity supply to tv, the companys have been going now for around 20 years, and do all kinds of things sofa's fridges ect, heres one of the bigger companys site. http://www.bayv.co.uk/
boy do i feel dumb now lol. ofcourse i need to id the vss and vdd before i can do anything. im used to knowing the part im dealing with and only having to figure how to read it,
some background the system is a prepaid meter of sorts, long story short, here in uk we have companys that offer tv's ect on credit on a pay per view basis. ie the meter controls the mains to the tv's, you add credit to the meter and it takes £x.xx per hour to pay for the tv, once the credit in the meter has run out you have to buy more and topup meter.
the token/key what ever you want to call it goes into a machine in the company and they add the credit manually ie they enter the amoutn of credit on a keypad, you then insert the token into the meter and it reads and adds the credit to the meter. if other data is transfered/stored i have no idea atm,
when i get my hands on a meter later ill have a look and see if i can get some more info, and id the vss/vdd and any other pins,
on a moral/legal stand there is nothign to be gained from hacking the system other than knlowdge, because if at the end of the month/week you havent paid the company enough for credit you must pay them with cash/card the remainding amount, so im not worried about anyone abusing the system as its pointless,
[quote author="Sjaak"]Looks like everything is working again on the blog. I hope this will give us the opportunity to post all the blogposts that were waiting ;)[/quote] yes working here too,
http://www.usbfirewire.com/parts/rr-usb ... f-1ft.html that solves the power problem. if its for personal use then you can hot wire one or 2 of the usb posts (via suitable fuses) directly to the 5v+ on the psu, simply remove the + & - from the usb header and connect to the psu, obv this is not a fesible option for mas production projects but for own use its perfect.
all the front panel usb ports on my pc are high current 5A+ so i have no problems no matter what i plug in.
if its something i plan to use elsewhere i also add on a barrel jack/molex
anyways should be about £20 other parts i got a free sample from tyco electronics (perf board i had laying around think it was £3 from maplins) i spent no more that £30 buying and building this which is a lot cheaper than one from usbjtag or a jtagkey i did find this http://www.100ask.net/shop/english.html but no supplier outside of china (which is a shame as i would have liked one) as a nice cheap open ft2232 jtag
building the addon board was very easy, no resistors/caps just the connectors and a bit of wire (no idea how safe this is but it's works and no reason write the chip too often)
sccs i see you wrote £ so i'll guess your in uk if you buy a mini module do you want me to make you a copy of the daughter card with the bits i have left [/quote]
dont know if your still around these forums m8. give me a shout as cannot for the life of me get this mini module to work.
