Retro¶
A page to show how easy STM32 and Forth makes embedded design in the 2020’s.
AT89C2051 MCU¶
This was a 8051 with on board 2KB flash, a couple of timer counters, a USART, comparator, what a great mcu in the 90’s. It was far, far easier than wiring up a cpu, ram, rom, timers, I/O etc.
Features¶
Compatible with MCS®-51Products
2K Bytes of Reprogrammable Flash Memory, Endurance: 10,000 Write/Erase Cycles
2.7V to 6V Operating Range
Fully Static Operation: 0 Hz to 24 MHz
Two-level Program Memory Lock
128 x 8-bit Internal RAM
15 Programmable I/O Lines
Two 16-bit Timer/Counters
Six Interrupt Sources
Programmable Serial UART Channel
Direct LED Drive Outputs
On-chip Analog Comparator
Low-power Idle and Power-down Modes
Green (Pb/Halide-free) Packaging Option
In Circuit Programmer¶
I had to design and make all this, just so I could program the chip in-circuit using a PC. I used SDCC, a FLOSS C compiler.