The considerations -
1) Moving from Keil to GNU compiler, but C code not substantially impacted.
2) Total resources required, UDBs, etc.. For example in PSOC 4 there are
no PGAs, just bare OpAmps, no VDAC, just IDAC.
3) Comparison table attached.
4) 8051 core to a M0 core, better.
PSOC 4M vs 3 Comparison.jpg 117.1 K
Thanks for the information.
I have to investigate the impact of the PGA and VDAC lost for this application.
May be we will keep the PSOC3.
I prefer the PSoC5. The difference is the more modern CPU which comes as an ARM M3 processor, having real stack. The components compared to the PSoC3 are quite the same.
I haven't checked it in detail, but in general the PGA and VDAC are not lost. With the PSoC4 comparator you maybe can build a PGA, and there's also a 7/8-bit DAC if I remember correctly. This is for PSoC 41/42 - I don't know if the 4M series has more analog parts. If pricing doesn't matter you can use a PSoC 5LP as already suggested, but if it would fit into a PSoC4(M) device, I'd consider to use this.
You cannot use the comparator as a PGA unless you can, by using register
writes, switch in the compensation cap used in the OpAmp to insure its
phase margin does not vanish and you have an oscillator on your hands.
Investigation of Register TRM should answer that problem.
You can use a bare opamp and a mux and external G setting and feedback
R's to effect a PGA.
The IDAC with an external R becomes a VDAC, and it can be buffered with
an OpAmp configed as a follower.
The beauty of Creator it does not take a lot of effort to establish if a port
into PSOC 4 will fit, just try it.