#garfield Logs

Apr 19 2021

12:09 AM rue_mohr: THE FREAKING OFFSET IS SIGNED
12:16 AM rue_mohr: WTF
12:16 AM rue_mohr: WHO DOES THAT
01:28 AM rue_mohr: ScreenBLT:
01:28 AM rue_mohr: CALL TOTALCLEAR
01:28 AM rue_mohr: LD HL,#0X2D60
01:28 AM rue_mohr: LD BC,#LCDTop
01:28 AM rue_mohr: this has taken me 45 minutes to write
01:28 AM rue_mohr: I wont give up tho
01:28 AM rue_mohr: as long as it takes!
01:59 AM rue_mohr: OK!
02:14 AM rue_mohr: http://paste.debian.net/1194252/
02:14 AM rue_mohr: it alternates chips to double the write rate
02:39 AM polprog: which chips?
02:40 AM rue_mohr: THE SCREEN HAS 2 CONTROLLERS
02:40 AM rue_mohr: SORRY CAPS I'M CODING ASSEMBLER
02:40 AM polprog: 04:13 < Tom_L> the CS prof would just hate me i'm sure
02:40 AM polprog: the CS prof is like "what's a wattage"
02:41 AM polprog: rue_mohr: oh neat. hd44780?
02:41 AM rue_mohr: YEA X2 ON THE SAME DISPLAY
02:41 AM polprog: neat
02:41 AM polprog: how big is that display
02:41 AM rue_mohr: ONE DOES THE TOP TWO LINES, OTHER THE BOTTMO TWO
02:41 AM rue_mohr: 40X4
02:41 AM polprog: :o
02:41 AM polprog: cool
02:41 AM rue_mohr: yea
02:41 AM rue_mohr: I'm totally burned out now tho
02:42 AM rue_mohr: I been just staring at the code for like half an hour now
02:42 AM polprog: thats bad
02:42 AM rue_mohr: ClearScrnBuff:
02:42 AM rue_mohr: LD BlitCtr_OFF(IY),#160
02:42 AM rue_mohr: LD HL,0X2D60
02:42 AM rue_mohr: LD A,#' '
02:42 AM rue_mohr: CLEARLOOP:
02:42 AM rue_mohr: LD (HL),A
02:42 AM rue_mohr: INC HL
02:42 AM rue_mohr: DEC BlitCtr_OFF(IY)
02:42 AM rue_mohr: JR NZ,CLEARLOOP
02:42 AM rue_mohr: within the last hour I wrote that
02:42 AM rue_mohr: it clears the buffer for the screen data
02:42 AM rue_mohr: i'm going to be blitting it to the screen
02:43 AM rue_mohr: i think
02:43 AM rue_mohr: performance will tell
02:43 AM rue_mohr: I have to add the pushes and pops to save the modified reg's
02:44 AM rue_mohr: SEE HOW the IY allows you to work directly with memory locations and avoid registers?
02:44 AM rue_mohr: less the fact that the OFFSETS ARE SIGNED
02:44 AM rue_mohr: like wtf
02:45 AM rue_mohr: instead of 0-255, its -128 - 127
02:45 AM rue_mohr: with the screen clear
02:46 AM rue_mohr: I'm wondering if it should allow you to pass a value in A that it uses to fill the screen
02:46 AM rue_mohr: I think that would probably be more annoying than usefull
02:46 AM polprog: i should connect an lcd to the 8051
02:47 AM rue_mohr: YES!
02:47 AM rue_mohr: what do you have?
02:47 AM rue_mohr: OR A 7 SEGMENT array or a VFD array
02:48 AM rue_mohr: the vfd array has the most cred
02:48 AM rue_mohr: :)
02:48 AM rue_mohr: even its its a serial comm POS screen
02:48 AM polprog: i think i have hd44780 compatible vfd
02:48 AM polprog: and for sure i have a single line serial vfd
02:48 AM rue_mohr: PERFECT
02:48 AM polprog: that also does paralell transmission
02:49 AM polprog: ive got a whole box of VFDs, just need to make a power supply for them
02:49 AM rue_mohr: yea, I want to know why that last design didn't work
02:49 AM rue_mohr: that was frustrating
02:54 AM rue_mohr: maybe about thrusday I can test these
02:58 AM rue_mohr: gnight
03:12 AM polprog: night
04:00 AM Tom_L: morning
04:39 AM polprog: morning
09:24 AM rue_mohr: definitly dont want to bank ram!
09:24 AM rue_mohr: I do want to make a banked math lookup rom tho
09:38 AM aandrew: :-) no?
09:38 AM aandrew: come on, you love banked memory
09:38 AM aandrew: eveyrthing you need is always in the wrong damned bank
04:25 PM polprog: my keyboard appears to loose connection every now and then more and more often recently
04:25 PM polprog: i should open it up and replace the mini usb jack
04:25 PM polprog: its probably worn out
08:15 PM rue_mohr: keyboards!
08:17 PM Tom_L: handy little devices
08:33 PM aandrew: ba-dum-bum tish
09:16 PM rue_mohr: so
09:16 PM rue_mohr: we ran out of material before we ran out of time
09:16 PM rue_mohr: only ended up working an extra half hour
09:23 PM rue_mohr: so, I want to get a 16550 on the laptop then
09:24 PM rue_mohr: I'd like to do that other chip, but its an adapter problem
09:48 PM rue_mohr: ok, my clearscreen and blt functions seem to work
09:48 PM rue_mohr: the full screen rewrite *looks* basically instatnt
09:50 PM rue_mohr: wires keep breaking off the external i/f connector
09:51 PM rue_mohr: ok, so
09:51 PM rue_mohr: putchar should be pretty simple
10:11 PM rue_mohr: HMM
10:11 PM rue_mohr: i want to know if A is equal or greater than a value
10:11 PM rue_mohr: so I do a CP #80
10:11 PM rue_mohr: ..
10:13 PM rue_mohr: jp C will be less
10:14 PM Tom_L: A & C are regs?
10:15 PM rue_mohr: cp IS COMPARE
10:15 PM rue_mohr: ARG CAPS
10:15 PM rue_mohr: A IS A REG
10:15 PM rue_mohr: CP #80 IS COMPARE A TO 0X80
10:15 PM rue_mohr: ER DECIMAL 80
10:16 PM Tom_L: https://www.youtube.com/watch?v=-JU4Xxwv1TI
10:16 PM Tom_L: alternate to ballscrew?
10:17 PM rue_mohr: OH DEAR
10:18 PM rue_mohr: IV NEVER WORN OUT A NORMAL SCREW
10:19 PM Tom_L: the z on the sherline was showing some wear
10:20 PM Tom_L: but yeah it takes a while
10:25 PM Tom_L: why "P" ?
10:30 PM rue_mohr: COMPARE
10:30 PM rue_mohr: THE BALL SCREW?!
10:30 PM Tom_L: dec 80 is P
10:31 PM rue_mohr: NO ITS ACTAULLY 80
10:31 PM rue_mohr: ITS A CURSOR POSITION
10:31 PM rue_mohr: SORRY, CODING IN CAPS
10:32 PM rue_mohr: so I have a 160 character screen
10:32 PM rue_mohr: two controllers, top half and bottom half are different ones
10:32 PM rue_mohr: I'v made a 'cursor position' from 0-159
10:33 PM rue_mohr: first, I need to know if it lands on the top or bottom controller
10:33 PM rue_mohr: then, I need to know...
10:33 PM rue_mohr: the screen positions aren't 0-79 ea
10:34 PM rue_mohr: its 0 - 0x28 for the first line
10:35 PM Tom_L: mmm
10:36 PM rue_mohr: then 0x00 -> 0x27
10:36 PM rue_mohr: sadflkjlskjf
10:36 PM rue_mohr: first 0x00 -> 0x27
10:36 PM rue_mohr: second 0x40 -> 0x67
10:36 PM rue_mohr: there is a gap
10:37 PM rue_mohr: so, if the cursor is over position 0x28, I need to add..
10:37 PM rue_mohr: 24
10:37 PM rue_mohr: (dec)
10:41 PM rue_mohr: i'M GONNA Have a hell of a time checking this...
10:41 PM Tom_L: sounds like it
10:42 PM rue_mohr: SERIAL HAS TO COME NEXT
10:43 PM Tom_L: so all the buttons on the cheap kbd were attached to the face
10:43 PM Tom_L: i took the whole face off and scrubbed it in the sink and dried it with the air hose
10:44 PM Tom_L: the membrane wasn't one piece but one for every key so that was kindof a pita
10:44 PM rue_mohr: HMM
10:45 PM Tom_L: i was a little more careful with the northgate kbd (cherry switches)
10:46 PM rue_mohr: :)
10:46 PM rue_mohr: they are worth a fortune eh?
10:46 PM Tom_L: i have 2 and am not sure the state of the 2nd one
10:46 PM Tom_L: i will never wear it out
10:46 PM Tom_L: the keytops are smooth though
10:47 PM Tom_L: i even got spare 'home' keytops (the ones with the bump on them)
10:47 PM Tom_L: and have worn those out as well
10:47 PM rue_mohr: irrc keycaps for cherrry switches are plentifull
10:47 PM Tom_L: i got those a long time ago
10:48 PM Tom_L: when northgate PCs were a thing
10:49 PM rue_mohr: whats this about wear on z?
10:50 PM Tom_L: those brass 'nuts' on the back of the z slide
10:50 PM Tom_L: i replaced it once
10:51 PM rue_mohr: i thought you used ballscrws?
10:51 PM Tom_L: not on the original sherline
10:51 PM rue_mohr: acme?
10:51 PM Tom_L: i think so
10:51 PM Tom_L: whatever they sell default
10:53 PM Tom_L: i got a couple of those 'shredders' to try
10:55 PM rue_mohr: maybe its just wear-in?
10:55 PM Tom_L: no matter now, it's tucked away in a box
10:56 PM rue_mohr: lots of cycles on that 1997 machine
10:57 PM rue_mohr: tho, its not as tight
11:00 PM rue_mohr: so I'm into some castin
11:00 PM rue_mohr: no ideas yet
11:00 PM rue_mohr: it would be fun to send you some rough casts you could machine up
11:02 PM rue_mohr: OK, i WROTE IT
11:02 PM rue_mohr: it SHOULD positon the cursor in a linear way
11:05 PM rue_mohr: I get 128 functions in my dynamic function system
11:05 PM rue_mohr: I'm at 25
11:05 PM rue_mohr: :S
11:05 PM rue_mohr: A-3ROM.s:745: Error: <a> machine specific addressing or addressing mode error
11:05 PM rue_mohr: *sigh*
11:06 PM rue_mohr: forgot the #
11:07 PM rue_mohr: 0x2F87
11:07 PM rue_mohr: is my magic cursor position vlue
11:07 PM rue_mohr: address
11:07 PM rue_mohr: write a rom...
11:08 PM rue_mohr: I wonder how much memory I have left...
11:09 PM rue_mohr: almost 50%
11:15 PM rue_mohr: drat its crashing
11:15 PM rue_mohr: and corruypting the rom
11:23 PM rue_mohr: gonna start by rewiring that damn rom
11:41 PM aandrew: you're not into self-modifying code?
11:48 PM rue_mohr: NOT YET
11:53 PM rue_mohr: ok, first stage debugging, code is ok
11:53 PM rue_mohr: er ,its backwards
11:59 PM rue_mohr: I'm kinda confused, there is nowhere it could have lost control