#avr Logs

Jun 02 2022

05:49 AM con3_ is now known as con3
06:27 AM specing_ is now known as specing
07:30 AM Flecks: AT90S4433 - can't read with SPI, what could be the problem? I can see with scope XTAL1/2 has 1MHZ sine so clock seems to be working
07:38 AM twnqx: if you have sine and not rectangle that might already be your problem:P
07:38 AM Flecks: yep it's sine
07:41 AM twnqx: wow that's an old chip
07:41 AM Flecks: and when I touch XTAL1 with screw driver, it seems to start running code ;D
07:43 AM twnqx: is it below 0°C? it might fail to start if BOS is enabled, then :P
07:44 AM twnqx: sounds like the load capacitors might be bad, but if you see the sine wae... no idea
07:44 AM Flecks: nope, indoors at home
07:50 AM Flecks: maybe ISPEN is not set
07:50 AM Flecks: or how was that fuse called
08:05 AM polprog: Flecks: definitely needs load caps
08:05 AM polprog: And the xtal1/2 pins wont have a square wave on them. A sinusoidal or a slightly triangular shape is correct there
08:06 AM Flecks: you mean xtal caps? I have those...
08:24 AM polprog: Maybe they are wrong value..
08:32 AM Flecks: how to know what values should be for crystal and what for ceramic resonator?
08:34 AM Flecks: for crystal I think usually was 22pF
08:34 AM twnqx: for crystal is written in the crystal datasheet, and the IC datasheet will tell you if it's acceptable
08:35 AM twnqx: i personally just use oscillators with cmos outputs and don't care about such analogue things ;)
08:45 AM polprog: I just pick whatever caps work with the crystal
08:46 AM polprog: I dont have the datasheets for most crystals in the parts box
08:48 AM Flecks: I don't either