.. index:: retro,8051,8051:in-circuit programmer and emulator, burn: the 8051 programmer/emulator .. _retro: .. Created retro.rst: Wed 9 Feb 2022 18:12:07 AEDT .. Full Path: /home/tp/mecrisp-unofficial-doc/retro.rst .. Author Copyright 2022 by t.j.porter .. Made by /home/tp/projects/scripts/makerst.sh -->/usr/local/bin/makerst .. license: MIT, please see COPYING Retro ===== A page to show how easy STM32 and Forth makes embedded design in the 2020's. AT89C2051 MCU ------------- This is 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. .. image:: pics/retro/AT89C2051.jpg .. seealso:: :ref:`The 8051<8051>` 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 and Emulator (Burn) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ I had to design and make this,back in the 1990's just so I could program the AT89C2051 chip in-circuit using a PC. I used SDCC, a FLOSS C compiler, for the MCU and Gcc for the PC connected programmer below. As usual I used a Makefile to orchestrate everything, so when I has written C code on SDCC for the AT89C2051, i.e. a stepper motor driver, I would enter 'make' on the pc and the running stepper motor connected to the programmer would stop for about 1/2 a second while the AT89C2051 was reprogrammed and then the motor would start running again. .. image:: pics/retro/burn-schematic.jpg It took me months to design the hardware and write the C source for the PC part but you get all this in a instant with Cortex-M MCU and a $2.80 AUD USB-SWD dongle like this St-link V2 Chinese Clone for Cortex-M Programming and IN-Circuit Debugging with GDB ----------------------------------------------------------------------------------- Usually has a APM32F103 or CKS32F103 and the latest STM firmware fitted. .. image:: pics/st-link_dongle.png