Search found 88 matches

by ijabbott
Mon Sep 10, 2018 6:40 pm
Forum: Hardware issues
Topic: Battery life
Replies: 18
Views: 1340

Re: Battery life

It sounds a bit like a leaky capacitor somewhere.
by ijabbott
Tue Aug 28, 2018 9:51 am
Forum: Usage tips, tricks and problem reports
Topic: DM42 - display contrast
Replies: 6
Views: 273

Re: DM42 - display contrast

I suppose the question remains why your display is "too dark", since the contrast on these displays is generally very good when viewed in well-lit conditions, certainly better than the contrast on the old HP-42S and similar two-line display Pioneer models, which wasn't that great.
by ijabbott
Thu Jul 12, 2018 7:10 am
Forum: Hardware issues
Topic: Need a replacement LCD
Replies: 5
Views: 527

Re: Need a replacement LCD

It might not be the ribbon cable. It might be the connector. If so, buying a new LCD wouldn't help.
by ijabbott
Sat Jun 30, 2018 6:15 pm
Forum: DM42
Topic: Countdown
Replies: 13
Views: 792

Re: Countdown

If register space was an issue (which it probably isn't), you could pack a few small integers (5 bits each) into a single register.
by ijabbott
Sat Jun 30, 2018 2:26 pm
Forum: DM42
Topic: Countdown
Replies: 13
Views: 792

Re: Countdown

Well, if you want to pick any letter from A to Z, you just need to pick a number from 65 to 90 and do XTOA. But I suspect you want to pick either a vowel or a consonant, so that doesn't work without a bit of manipulation. So in that case, using registers is probably easiest. You'd only need 5 regist...
by ijabbott
Sat Jun 30, 2018 11:35 am
Forum: DM42
Topic: Countdown
Replies: 13
Views: 792

Re: Countdown

I'm familiar with Countdown. I even watched the first show when Channel 4 started. (It was such a novelty at that time in the UK to have a choice of four TV stations!)

Anyway, I'm wondering why you need to store the alphabet.
by ijabbott
Wed Jun 27, 2018 7:13 pm
Forum: DM42
Topic: Countdown
Replies: 13
Views: 792

Re: Countdown

Is that normal Countdown or "Street Countdown"?

https://youtu.be/0-GRjNocLs8
by ijabbott
Sat Jun 16, 2018 5:42 pm
Forum: Developer Forum
Topic: DMCP_SDK Hello World
Replies: 20
Views: 1219

Re: DMCP_SDK Hello World

What if you add -std=c99 or -std=c11 ? But what is a policy of DM42 SDK - are we C99 compliant? With following options: CFLAGS += -std=c99 CFLAGS += -pedantic-errors DMCP_SDK$ make arm-none-eabi-gcc -c -mthumb -march=armv7e-m -mfloat-abi=hard -mfpu=fpv4-sp-d16 -D__weak="__attribute__((weak))" -D__p...
by ijabbott
Thu Jun 14, 2018 8:38 pm
Forum: Developer Forum
Topic: DMCP_SDK Hello World
Replies: 20
Views: 1219

Re: DMCP_SDK Hello World

Build with -pedantic-error compiler option: DMCP_SDK$ make arm-none-eabi-gcc -c -mthumb -march=armv7e-m -mfloat-abi=hard -mfpu=fpv4-sp-d16 -D__weak="__attribute__((weak))" -D__packed="__attribute__((__packed__))" -Idmcp -Isrc -Wall -fdata-sections -ffunction-sections -Wno-misleading-indentation -pe...
by ijabbott
Tue Jun 05, 2018 9:52 pm
Forum: DM42
Topic: Question about "what goes where" while flashing firmware
Replies: 6
Views: 497

Re: Question about "what goes where" while flashing firmware

Where do the files of the pattern DM42-<m>.<n>.<o>.pgm go...?? These are -- as far I understood the split -- the parts containing Free42 and therefore the most changed once...? They get written to some Flash memory by the DMCP "Load Program" code (which is in also in Flash memory). The code might c...