[SOLVED]What was your first micro programming experience?

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Pushkar1

Joined Apr 5, 2021
401
My first attempt with micro was very bad. I started with microcontroller on the breadboard. I wrote c code for LED flashing but When I tested it on the Breadboard. LED was not flashing. After that I try the same code on the development board then the led was flashing.

This was my first experience of learning

What was your first micro programming experience?
 

Ian0

Joined Aug 7, 2020
3,752
Writing 6502 code for a Commodore PET, assembling it by hand and entering it as hexadecimal (back in 1980). I was astonished how fast it ran compared to a high-level language (which, at that time, was BASIC)
 

Dave Lowther

Joined Sep 8, 2016
104
What was your first micro programming experience?
In about 1978 I designed and built myself a very basic Z80 board. It had switches to DMA a byte into RAM and some LEDs to show RAM contents. Programming that was a bit tedious and the program was lost if the board was powered off.

After that I think the first actual microcontroller I programmed was the 8051. I had to get the hex file output from the linker and use it to program an EPROM. To modify the code I had to put the EPROM in a UV eraser to clear it before trying a new version of the code. " But you try and tell the young people today that... and they won't believe ya'. " (Python)

Nowadays it's so easy to get started and get a project working really quickly, particularly with the Adruino hardwre, IDE, and libraries. Luxury!
 
The DEC PDP-8 and PDP-11 mini-computers don't count , right?

Motorola 6800 (class): interface a LED display and keypad

COSMAC 1802: Microprocessor controlled gantry crane for a model railroad. Didn't use a compiler. Compiled code by hand. Entered via a keypad. Later did the the project with a Vitrax IX SBC with better crane hardware.
 
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Ian0

Joined Aug 7, 2020
3,752
First real "microcontroller" was the original PIC16C54, with half a K of EPROM and 64 bytes of RAM. I wrote a 250kbaud UART in software and output timed pulses to four servo motors for DMX controlled disco lighting.
Nowadays I use ARM Cortex M3, but I still prefer assembler to C. After 5000 lines of code, I'm left thinking "What do I do with the other 240k of FLASH?"
 

Irving

Joined Jan 30, 2016
2,308
Wasn't my first (8080/Z80/6502/etc) but most memorable - 1979/80 Programming a MIL-spec, radiation hardened RCA1802 in assembler on 5-bit punched tape loaded two nibbles at a time direct to memory, as part of an ongoing development for an experimental 'intelligent' air/ground telemetry system..... no IDE, high-level langage, in-circuit debugger, or any of the niceties of today's platforms, just 9 months of hard, frustrating, slog...
 

Irving

Joined Jan 30, 2016
2,308
8080, RCA1802, 6502, 8085
"some day we will see 1 millions instructions per second"
Yeah, some days it was like watching paint dry....... :)
Loading 16k of memory from a 300bd tape reader every time the code was changed (54min approx) was kind of soul destroying though we did improve on that over time - I designed & built a 'virtual tape reader' interface from RS232 @ 9600bd using an 8251 UART which got it down to 30sec...
 

BobTPH

Joined Jun 5, 2013
4,030
Never done any microprogramming which is not what you think it is.

First micro-computer program was porting a COBOL runtime interpreter to 8086.

First microcontroller programming was a NiCad battery charger controlled by a PIC. Fell in love.

Bob
 

Papabravo

Joined Feb 24, 2006
17,240
In 1972 we built an IBM 3270 terminal emulator with an Intel 8008 running at 487.5 kHz in assembly language. Wading through the IBM documentation in those years was the kind of thing a young engineer could really sink his teeth into. Hooking the machine we built to an IBM mainframe with no complaints from the mainframe and selling for a fraction of the cost of an actual 3270 was a tour de force.
 

dendad

Joined Feb 20, 2016
3,939
My first was based on a Signetics 2650.
2650_01.png
The kit was from the Electronics Australia may 1978 mg.
https://archive.org/details/EA1978/EA 1978-05 May/page/n57/mode/2up
I did not build it, but swapped an IBM Selectric printer for it.
This was a great learning device, running via a 110baud "TV Typewriter".
One early update was to go to 300baud.
Then, replaced the Kansas City cassette interface for a much faster (and simpler) bit banged on that ran at 5Kbaud.
The RAM was expanded to 11K that was 88 x 2102 1K x 1bit chips on 4 daughter boards that stacked onto an S100 mother board that was wired into the EA kit PCB RAM holes.
I was very proud on myself as I re-wrote the 1K monitor to add 3 extra commands.
Then, built a memory mapped video driver based on a 6847 chip.
For a long time, a model 15 teleprinter was my printer.
More additions were an EPROM programmer, originally to use 2708 1K x 8 EPROMS, then 2716 and 2732 parts.
The EPROM programmer was very simple as the 2650 is static so a block move can be used with the processor halted while the EPROM programming signals were cycled.
Quite a few hours were spent typing in HEX listings from EA to install a dissasemble then a line assembler. All stored on cassette.
For some reason I cannot now fathom, I gave it all away years ago. I wish I still had it :(

This was replaced with a Rabble Ozi (based on the Ohio Scientific 6502) kit that a couple of friends on mine here in Oz designed.
This had 48K RAM using 6116 2K x 8 chips, and a floppy drive. I built this into a "Brighter Writer" (that really was its name) printer, so I had about the only luggable computer with inbuilt printer.
It included a roll of paper, not sheets.
Ah! The old days.
But I did learn a lot.
 

MrChips

Joined Oct 2, 2009
24,609
RCA 1802, MCS6502, MC6805.

One of my earliest MCU project was to program an RCA 1802 in asm by hand to scan a Microswitch keyboard and send ASCII to a CP/M Z80 micro running WordStar text editor. Single key strokes were programmed to send ESC codes for text editing and formatting.
 

MaxHeadRoom

Joined Jul 18, 2013
23,906
Mine was a PDP-8 also, you could 'see' each physical bit of (magnetic core) memory !!.
But mainly the 8081/8085 where there were no internal accessory modules, A/D, I/O USART etc, all were separate devices.!
 

AlbertHall

Joined Jun 4, 2014
11,594
The first processor datasheet I read was for the Z80 but I found it much too difficult to understand.
Then I came across the scamp and I made PCBs for the processor, a 1k (!!) RAM board, LEDs (1 per bit) to see what was going on, and some binary buttons to enter programs. I had to re-enter the program every time I switched it on.
Then Sir Clive Sinclair released his Z80 based computers so I looked again at that datasheet and now I could understand it so those were the next processors I wrote programs for then, at work, for Commodore 64 and PET...
 

Ian0

Joined Aug 7, 2020
3,752
The PIC is a much older device that you might think - it started life as a support chip for a General Instruments processor back in 1976 - it stands for "peripheral interface controller" - and was originally fabricated in NMOS.
 
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