Okay, sometimes my oscillator will not kick in at 3V. If I remove one of the caps on the crystal it will start oscillating (and continue even after I put the cap back in place).
I'm using 22 pF caps. Should I go with less capacitance for 3V? I'm asking here because I have to order these parts online and wait a few days, so trial and error wastes a great deal of time.
I have to run faster than 4 MHz. The device I am interfacing requires communication at 250 kHz, which I cannot achieve at 1 MIPS. I should be able to modify my code and manage to do 250 kHz at 2.5 MIPS (10 MHz).
I have to run faster than 4 MHz. The device I am interfacing requires communication at 250 kHz, which I cannot achieve at 1 MIPS. I should be able to modify my code and manage to do 250 kHz at 2.5 MIPS (10 MHz).
Table 1-1 of the PIC16F62X datasheet seems to state the 16LF628 having a maximum operating frequency of 20MHz. Is there really a need to get the A-version?
A USART is both syncronous and asyncronous, as opposed to a UART which is just asyncronous. So it's quite possible you could use the USART in syncronous mode for the job, try having a read of the datasheet and mid-range reference manual.
You could probably also run it easily in software, but slower than you have been trying - with a syncronous serial system like this the host generates the clock, so the speed doesn't really matter, it's simply how fast you supply the clock pulses. The 250KHz you were talking about seems far too fast for a simple game controller?.
It's 250 kHz. The bit width is right around 4uS, when scoping a PSX console communicating with its controller. I've got things working perfectly bit banging via software. However I'm very tempted to see if I can maintain the necessary 250 kHz @ 8 MHz, so I can go with the PIC16F819 and just use the internal oscillator. That should be achievable.
Yes, I'm hosting the controller - an actual console is not involved. Yes, a Sony brand controller will properly operate at significantly lower clock speeds. However some 3rd party controllers (specifically MadCatz, which is very prevalent) do not. They have to run at or about the speed a PSX communicates at - 250 kHz. My interface must work with any PSX controller regardless of brand.