I’ve been through distributor parametric selection (annoyingly incomplete criteria and inconsistent results) and manufacturer product selectors (tedious to use and unreliable pricing). Now I’d like to try the collective wisdom of the forum.
Help me find an optimal micro controller please.
Requirements:
* Bi-directional GPIOs: 36 minimum (or 32 + one SPI on separate pins)
* Flash-based. In-circuit programmable (ICP).
To be optimized:
* Price: Current leader is US $1 Q100.
* Package: SMD, but somewhat friendly e.g. QFP/SO, QFN if necessary.
* Internal oscillator if possible.
* ICP requires no programmer and can be bit-banged (i.e. protocol is disclosed).
Don’t care:
* uC speed as long as > 1 MHz.
* uC architecture or flash program capacity. My program will only be a few dozen instructions long.
* No program development tools required (dev env, compiler, assembler etc.)
The current leader is a Microchip AT89LP51. Yes, 8051-based
But that part is dead-simple and familiar. It’s perfect: TQFP-44, 33 GPIOs + ICP/SPI, 1.8 MHz internal osc, no other junk to get in the way. I need to emulate a function similar to a 74LVT18512 (discrete boundary scan chip). But without it costing $6 a pop as I will need many of these. Also, I don’t care about JTAG compatibility & speed.
Can anyone beat the AT89LP51 at $1?
Thanks.