New Convoy C8 – Clearly better

The new ones with Biscotti don’t do that. When we started using he Off-time capacitor it was to do away with that. All the old Nanjg 105’s and Qlites had that type of action, you had to bump it twice to nudge it forward after it’d been on for a bit.

Biscotti in the new Convoy’s brings a wealth of change, virtually all good. :wink:

As far as I can tell, there wasn’t actually any intent behind that. It was an unfortunate side effect of the way it implemented memory.

The “on-time memory” it used worked like this:

  1. Light turns on. Read the mode number from eeprom, and go to it.
  2. Write the mode number plus one to eeprom.
  3. Wait a second or two.
  4. Write the current mode number to eeprom.
  5. Wait forever.

So, if you leave it on for more than a second or two, next time you use it it’ll go to the same mode. If it was on for less than a second, it goes to the next mode. It doesn’t attempt to measure how long it was off.

Biscotti uses off-time memory instead. The behavior is determined by how long the light was off. So, during use, a quick tap always goes to the next mode. This is almost universally preferred. The main downside is that it’s more sensitive to what happens while the power is off, so a lighted tailcap can interfere with the “off time” measurement.

Very interesting, thanks for explanation DB Custom and Toykeeper.

If it is writing something to eeprom every time we switch modes, could the memory eventually ‘wear out’ ? Or is eeprom write endurance sufficiently high for this not to be a problem during a typical lifespan ?

I don’t know if the old 3/5-mode firmware uses wear leveling. If so, the ROM should take at least a few centuries to wear out. If not, it should still take at least a decade. And those are both low estimates. Biscotti should take nearly a thousand years, even with quite a bit of daily use, before it ever starts thinking about having eeprom wear issues.

<—— filling out post-it note that TK guarantee’s Biscotti for 1000 years, logging it at 4/28/2017.

I’ll be watching you! :stuck_out_tongue:

Dale, I’m afraid to see what your post count will be 1000 years from now. I’m guessing it’ll cause an overflow at some point :stuck_out_tongue:

?huh ,tnuoc ym fo emos ecuder ot redro ni sdrawkcab gnihtyreve gniyas trats ylbaborp dluohs I

I don’t think it works that way :partying_face:

(man, after a bit of Sobieski, that took a minute to process!)

ROFLMAO!

I had the standard text on standby, just in case. :stuck_out_tongue:

Y’all are soon to be on vacation from my ever present wit so enjoy it while you can. :wink:

So, the eeprom is rated for 100,000 erase/write cycles minimum per byte… but in actual testing people tend not to encounter any failures until more like 10 million write cycles. So take 100k as a lower bound and 10M as an upper bound.

With only 32 bytes used for wear-leveling, let’s find out how many times a day you’d have to press the button to make it fail in 1000 years or less:

  • 100,000 * 32 / 365.24 / 1000 = 8.76
  • 10,000,000 * 32 / 365.24 / 1000 = 876

So… to make it fail in 1000 years, you’d have to press the button at least 8.76 times per day (every day) or potentially up to 876 times per day. I’m pretty sure some other part of the light would wear out first, like … the switch.

I didn’t care for it either. You can reflash it with a different firmware like guppydrv for instance or swap to a driver that has different firmware on it.

Both my S2+ and black C8 have guppydrv and it’s great.

guppydrv lacks low voltage protection though, something to be aware of….

Really? This is the first I’m hearing of it.

For example, on MTNs website for the Qlite driver it says the driver has low voltage protection then it says guppydrv is an option. It doesn’t say you lose the LVP with this firmware.

Maybe Richard should point this out as I had no idea.

In my 2 lights that have guppydrv I use protected cells. The one I’m working on right now, I had planned to use an unprotected one. I guess I can switch to a protected battery for it. Ah wait, that one was gonna use 2 26350 which are unprotected only. I may need to switch to a different firmware.

Thanks for the heads up.

Richard DOES point that out. He states that the light will downshift but will not turn off.

Which means that it’ll run in the lowest mode till the battery is dead.

If you use the newest Bistro you’ll have a similar number of mode choices, it’s on the list as 9 but by changing H-L/L-H you’re doubling the list. Bistro allows you to set it up as you like, at will, including changing memory by toggling it on or off. You decide if it has 2 levels or 3 or 4 or 5 or 6 or 7 or 8 or 9, at will. You decide if it has moon or not. Also gives you choices with strobes, in a hidden group you back into. And the ability to reverse to a lower mode can go a LONG way towards saving battery life. Bistro is also on an FET+1 driver, so your lower modes are more efficient, pulling from a single 7135 chip instead of 8 or the FET.

Okay, so guppydrv has more of a low voltage warning as opposed to low voltage protection. You’ll know when the battery gets too low, but if the light gets turned on by accident and you don’t realize it, then it can drain the battery dangerously low. Is that correct?

Pretty much, yeah.

When the light is on a higher level and the cell is draining you can usually see that and you’ll know, but by shifting down to lower modes you don’t notice the dimming, so say it shifts down and you’re still fishing, still using the low to bait hooks and what not. The light stays on, you forget it’s on low by it’s own device and in the morning you find your cell at a shocking 2.1V. Oops! Some chargers will accept this, some won’t. An isolated occurrence like this shouldn’t do harm to the cell, but there ya go, it’s up to you to monitor it where true low voltage protection will shut the light off at a safe cell level.

It’s a plus in some cases, you don’t have total darkness without warning, but of course you’re supposed to stop and swap cells when it drops down… you DO have a spare with you, don’t you? :wink:

Spare cells?
Shoot, I got spare flashlights!
3 or 4 spare lights just in case.

Three generations of Convoy C8 flashlights

Gotta love em!

I’m betting on Simon having some new stuff for us, he’s alwys on top of things and seems to like lights as much as we do!

Take my money Simon, please! :smiley:

I agree with you Dale, i am always excited when i see something new from Convoy because: a) it is not going to cost an arm and a leg; b) it is going to be very good quality; c) when properly modded it is going to put to shame everything in that price range.

Anyways i do really like to see proper thrower from Convoy, not that the L2 or even the L6 when modded are bad but i do want something that can push 500kcd or even more :slight_smile: