PIC14 edit, added save after hexload - UK Vintage Radio Repair and Restoration Discussion Forum

Phil__G · 28th Nov 2022, 11:15 pm

It seemed strange to me that only manually keyed in programs were kept non-volatile. If you hex-loaded a program, it disappeared with the power off.
If you wanted to take your PIC14 to a show with a pre-loaded demo, say "Duckshoot", you couldnt hex-load the demo at home - you'd have to key it in manually, or hexload it at the show!
I dont think Karen did this deliberately, I think the intel hex loader was probably a 'late addition' to the firmware. Anyway this edit saves the hex-loaded program.
Its on the "Karen Orton 'PICL' NIBL Computer & PIC14 files" page of http://philg.uk right at the bottom of the page.

Phil__G · 29th Nov 2022, 1:49 am

Forgot to say, when a new PIC is programmed for the very first time, ie nothing has yet been manually keyed in or hex-loaded, rather
than leaving it empty, the non-volatile ram defaults to the Science of Cambridge Message demo from the MK14 manual.
This is overwritten as soon as any new program is keyed in or hexloaded.
So you can blow a brand-new pic, plug it in, press the "SC/MP Reset" button, type F 2 0 and Go, which if nothing else is a quick test,
confirming that indeed "as you can see the S of C is a jolly fine buy"
Cheers
Phil

Realtime · 22nd Feb 2023, 5:55 pm

I just posted a quick 2 minute video of the building of my PIC14 module. Very nice project and worked first time. It was great having the demo program already installed.

Next thing to try is the hex loader

Timbucus · 22nd Feb 2023, 9:17 pm

Yea nice liked the time lapse of the components being added

Phil__G · 22nd Feb 2023, 10:24 pm

Yes that was very effective!

Realtime · 25th Feb 2023, 5:10 pm

Quote:

Originally Posted by Realtime

Next thing to try is the hex loader

So the hex loader is working. I assume PIC14 doesn't recognise the execution address tagged at the end of the hex file? Currently PIC14 boots back to 0000 00 after a load.

I was trying to load a hex file that spanned the 0xB00 and 0xF00 RAM areas, only to eventually find this statement on Karen's site "although the PIC14 RAM features several times in the memory map, they are just copies – there is only 256 bytes of RAM in total". Explains why when I loaded Moon Lander ('George' version of course) I found it mirrored in the 0xB00 area. I must learn to read the documentation first

SiriusHardware · 25th Feb 2023, 6:12 pm

Quote:

I assume PIC14 doesn't recognise the execution address tagged at the end of the hex file?

No, that 'convention' of having the execution address stored at FFFE/FFFF in the file only came about with my Pi-uploader, which Karen's PIC14 pre-dated by some years.

Phil seems to enjoy tweaking the PIC14 code though, so....?

Realtime · 21st Mar 2023, 7:05 pm

Some photos of my PIC14 fully dressed. It's actually a red LED display but the camera can't handle it.

To have a single letter for every key I used
P: PIC reset
R: MK14 reset
X: Abort

Attached is the hex file for displaying PIC14 on the 7 segment if anyone wants it. Loads and runs from 0F20.

It waits for a key press before returning to the monitor but only keys 2, 6, 8, C, F are detected as valid. The others are ignored. PIC14 keyboard decoding strikes again

28th Nov 2022, 11:15 pm	#1
Phil__G Hexode Join Date: Mar 2011 Location: North Yorkshire, UK. Posts: 498	PIC14 edit, added save after hexload It seemed strange to me that only manually keyed in programs were kept non-volatile. If you hex-loaded a program, it disappeared with the power off. If you wanted to take your PIC14 to a show with a pre-loaded demo, say "Duckshoot", you couldnt hex-load the demo at home - you'd have to key it in manually, or hexload it at the show! I dont think Karen did this deliberately, I think the intel hex loader was probably a 'late addition' to the firmware. Anyway this edit saves the hex-loaded program. Its on the "Karen Orton 'PICL' NIBL Computer & PIC14 files" page of http://philg.uk right at the bottom of the page.

29th Nov 2022, 1:49 am	#2
Phil__G Hexode Join Date: Mar 2011 Location: North Yorkshire, UK. Posts: 498	Re: PIC14 edit, added save after hexload Forgot to say, when a new PIC is programmed for the very first time, ie nothing has yet been manually keyed in or hex-loaded, rather than leaving it empty, the non-volatile ram defaults to the Science of Cambridge Message demo from the MK14 manual. This is overwritten as soon as any new program is keyed in or hexloaded. So you can blow a brand-new pic, plug it in, press the "SC/MP Reset" button, type F 2 0 and Go, which if nothing else is a quick test, confirming that indeed "as you can see the S of C is a jolly fine buy" Cheers Phil Last edited by Phil__G; 29th Nov 2022 at 1:55 am.

22nd Feb 2023, 5:55 pm	#3
Realtime Pentode Join Date: Jan 2021 Location: Ashford, Kent, UK Posts: 148	Re: PIC14 edit, added save after hexload I just posted a quick 2 minute video of the building of my PIC14 module. Very nice project and worked first time. It was great having the demo program already installed. Next thing to try is the hex loader

22nd Feb 2023, 9:17 pm	#4
Timbucus Octode Join Date: Mar 2019 Location: Barry, Vale of Glamorgan, Wales, UK. Posts: 1,269	Re: PIC14 edit, added save after hexload Yea nice liked the time lapse of the components being added

22nd Feb 2023, 10:24 pm	#5
Phil__G Hexode Join Date: Mar 2011 Location: North Yorkshire, UK. Posts: 498	Re: PIC14 edit, added save after hexload Yes that was very effective!