Are some Attiny based drivers locked?

Flashlight Modding and DIY Parts
1

I have re-flashed the Nanjg and Qlite drivers I have bought from mtnelectronics.com. Right now I could use a couple of nanjg 4*7135 drivers for a little project but mtnelectronics is out of stock. I have some Qlite with 8*7135 I could use but I don’t need the 8 and would rather not just remove them… seems like a waste.

My memory is fuzzy but I seem to recall reading here someplace that some attiny based drivers being sold may be locked, so they cannot be reflashed. I’ve tried searching the forum and have not come up with an answer.

Can anyone fill me in on whether or not that is true?

Where/who would be a good source for some drivers like the Nanjg 101-AK-A1 with 4*7135’s that can be reflashed?

Thanks for the help.

2

The only issue I recall is some driver PCBs have the reset pin tied to power or ground, and that needs to be cut to get it flashed.

3

13A's can be locked so our typical USB dongle are made inoperative to program them. You need the special Atmel kit, think the Dragon, to unlock them. So yes - they can be locked. You can even accidentally lock them based on fuse settings. I know, I bought some off of eBay that were locked - seller didn't understand but Richard at MtnE unlocked them for me (he has the Dragon tool), then I could program them.

4

The lock can be removed with any ISP programmer. Only if the chip was configured for high voltage programming it requires a special programmer.

5

Thank you all.

6

Here: https://arduinodiy.wordpress.com/2015/05/16/high-voltage-programmingunbricking-for-attiny/

You'll have to provide some explanation because this is what I, and others, understand. Once you program pin #1 as an I/O pin, you brick the MCU.

7

I thought that after uploading a new program, the attiny unlock itself.

8

For example the ATTiny85 datasheet, section “20.1 Program And Data Memory Lock Bits”.

9

The term “lock” is somewhat misunderstood here. As you wrote; programming pin #1 as IO bricks the MCU, it doesn’t lock it. Setting pin #1 as IO has no effect what so ever on the lock bits, just as locking the MCU with the lock bits does not brick the MCU.

Locking and bricking are not the same thing. A bricked MCU requires high voltage programming in order to flash again, a locked MCU doesn’t. According to the datasheet, a chip erase is enough to reset lock bits:

10

Guess we are missing the point of the OP. Call it whatever, but the fact is the driver can't be re-programmed - do you guys at least agree that it's possible?

Just change the prior words from "locked" to "bricked" please... This is kind of silly since you guys are arguing semantics while the OP points out a real world problem of not being able to reprogram drivers.

11

Yes, there are some drivers that have the lock bits set. They require an explicit chip erase to be reflashed.

I have not seen a driver that has serial programming disabled. Thus a normal ISP programmer should always work.

I have seen drivers, that have some ISP pins grounded, for example pin 5 (MOSI) on some Convoy drivers.

12

That's not answering the question, ok, that's it for me...

13

I have bricked some chips when I slipped off with the SOIC clip during flash cycle
If the reset pin is set to I/O the flash stick can’t communicate to the MCU anymore properly, so it should work with existing code but flashing again is not possible

There are a lot of drivers that are locked by PCB design shorting some flash relevant pins to ground

14

Maybe you have misunderstood the question?

15

Let me rephrase my original question.

First, I have not reflashed many drivers. In fact, the only drivers I have flashed are Qlite 105C and Nanjg (47 or 101 variants) than I have bought from mtnelectronic.com.

I want a couple of Nanjg101's in the next month or so, but mtnelectronics is out of stock.

If I buy some nanjg 101's from, say, fasttech, KD, a seller on ebay or aliexpress, are the chances good that those MCU's will be reflashable?

The question is raised because of my fuzzy memory and limited experience. It's one of those situations where a little knowledge (my remembering something about a problem reflashing something) can be a dangerous thing. (making me wonder if the fuzzily remembered incident has any bearing on what I wish to do).

So, in short form, if I buy a Nanjg 101 from any of the common parts vendors will I very likely be able to reflash it?

If you have bought and reflashed that should be a simple "yes" answer. OR, if you have been unable to reflash a attiny based driver which ones? Somebody mentioned a problem with some Convoy branded driver. Maybe that is what I recall, but I don't recall the specifics.

Thank again.

16

nanjg 101 fast tech review

17

Thanks.

Does anyone have a recommendation for any other reflashable 4*7135 attiny based driver that they like better for some reason? 17mm

18

i had a heated argument on another forum about that, i was told that 8 amc is too much for a small flashlights, and i should get 4 or 6, or remove some. i was arguing that, i’d rather have 8 and use mid level rather than removing 4 chips, and if i ever need to i can use all 8. but i was told, that when i use pwm to dim the light in such driver, efficiency of pwm will be lower than have no pwm but less amc chips. we never figured how much less efficient, if it even worth considering.

19

The thing to remember about 7135 is that they don’t magically guarantee constant current. They can’t create amps that don’t exist.
If you install 8 of them, that is a power REQUIREMENT of 2.8 amp at all times, even when the battery is low or has high IR (or both).
If you have (4) 7135, that is a power requirement of 1.4 amp at all times. Most batteries can provide that without stress.

20

I only want 4 for this application.