PASM - Writing to HUB RAM
lanternfish
Posts: 366
Hi all. A bit of a newbiewith PASM so bear with me.
I have an annoying issue with writing a 'table' to HUB RAM. I can't see where I have gone wrong and thought (a) fresh brain(s) could help.
Attached is PASM to read RGB data from a FIFO buffer (no addressing needed). The data format is 00000000_00rrrrrr_00gggggg_00bbbbbb. The FIFO RD pulse is on P7.
The first major part of the code reads in the data and stores it in COG RAM from $100. This appears to work fine.
The second major part (below) reads two longs from COG RAM, averages the two bytes and is meant to store it in HUB RAM from $0000. It doesn't! It stores it from $100 and the number of longs stored is inconsistent. It should be 100.
Any advice with sorting this problem will be much appreciated.
EDIT: Corrected HUB RAM - COG RAM comment error (as pointed out by Ale #2)
I have an annoying issue with writing a 'table' to HUB RAM. I can't see where I have gone wrong and thought (a) fresh brain(s) could help.
Attached is PASM to read RGB data from a FIFO buffer (no addressing needed). The data format is 00000000_00rrrrrr_00gggggg_00bbbbbb. The FIFO RD pulse is on P7.
The first major part of the code reads in the data and stores it in COG RAM from $100. This appears to work fine.
{{DecimatePixels}}
PUB Main
{Launch cog to DecimatePixels}
cognew(@ReadFIFO, 0) 'Launch new cog
CON
_clkmode = xtal1 + pll16x
_xinfreq = 5_000_000
DAT
{ReadFIFOData}
org 0 'Begin at Cog RAM addr 0
ReadFIFO mov dira, FIFOReadPin 'Set P7 output (FIFO RD pulse +ve)
mov outa, #0 'P7 Low
GetRGBData xor outa, FIFOReadPin 'P7 High
nop 'Wait for data to settle
' mov RGBValue, ina 'Read RGB value from FIFO and store at address RGBAddress
mov RGBValue, PseudoIna 'Store pseudo-ina data at address RGBAddress
xor outa, FIFOReadPin 'P7 Low
WriteTable movd WriteRGB, COGPointer 'Prepare self modifying code that
nop 'will write RGB data to COG RAM
WriteRGB mov 0-0, RGBValue 'Write RGB data to COG RAM
add COGPointer, #1 'Point to next COG RAM address
djnz PixelCounter, #GetRGBData 'If PixelCounter not zero then repeat @ GetRGBData
SignalNextCog wrbyte NextCOG, COGSync 'COGSynch Address = $1FFF: HUB RAM Cog Synch address
The second major part (below) reads two longs from COG RAM, averages the two bytes and is meant to store it in HUB RAM from $0000. It doesn't! It stores it from $100 and the number of longs stored is inconsistent. It should be 100.
DecimatePixels mov PixelCounter, #100 'Get ready to read 200 RGB longs (2 at a time)
mov COGPointer, #$100
DecimateLoop movs RGBRead1, HUBPointer 'Prepare self modifying code that
nop 'will read 1st RGB long from COG RAM
RGBRead1 mov RGBValue, 0-0 'Read 1st RGB long from COG RAM
add COGPointer, #1 'Next COG RAM address
movs RGBRead2, COGPointer 'Prepare self modifying code that
nop 'will read 2nd RGB long from COG RAM
RGBRead2 mov RGB2Value, 0-0 'Read 2nd RGB long from COG RAM
DecimatePixel add RGBValue, RGB2Value 'Add 1st and 2nd RGB longs
shr RGBValue, #1 'Divide by 2 (get average of two longs)
RGB2Table movd RGB2HUB, HUBPointer 'Prepare self modifying code that
nop 'will write RGB long to HUB RAM
RGB2HUB wrlong RGBValue, HUBPointer 'Write RGB data to [B]HUB[/B] RAM
add HUBPointer, #4 'Point to next HUB RAM long address
djnz PixelCounter, #DecimateLoop 'If PixelCounter not zero then repeat @ DecimateLoop
ForeverLoop jmp #ForeverLoop
PseudoIna long %00000000_00101010_00010101_00101010
NextCOG byte 2
COGSync long $1FFF
FIFOReadPin long |< 7
PixelCounter long 200
COGPointer long $100
RGBValue long $0000
RGB2Value long $0000
Any advice with sorting this problem will be much appreciated.
EDIT: Corrected HUB RAM - COG RAM comment error (as pointed out by Ale #2)
Comments
And this part...
RGB2Table movd RGB2HUB, HUBPointer 'Prepare self modifying code that nop 'will write RGB long to HUB RAM RGB2HUB wrlong RGBValue, HUBPointer 'Write RGB data to COG RAMWIll change the d-field of wrlong (it is the source, that is constant in your program, RGBValue).
It should be...
Ale
Will try it out.
RGB2Table movs RGB2HUB, HUBPointer 'Prepare self modifying code that nop 'will write RGB long to HUB RAM RGB2HUB wrlong RGBValue, 0-0 'Write RGB data to HUB RAMUse it as I wrote above. Here is the simulation, it did two cycles through the loop
Edit: **** NOTE *** There is a variable in COG RAM that is of byte size... make it long !
DecimatePixels mov PixelCounter, #100 'Get ready to read 200 RGB longs (2 at a time) mov COGPointer, #$100 DecimateLoop movs RGBRead1, [COLOR="Red"]COGPointer[/COLOR] 'Prepare self modifying code that nop 'will read 1st RGB long from COG RAM RGBRead1 mov RGBValue, 0-0 'Read 1st RGB long from COG RAM add COGPointer, #1 'Next COG RAM address movs RGBRead2, COGPointer 'Prepare self modifying code that nop 'will read 2nd RGB long from COG RAM RGBRead2 mov RGB2Value, 0-0 'Read 2nd RGB long from COG RAM [COLOR="Red"] add COGPointer, #1 'Next COG RAM address[/COLOR] DecimatePixel add RGBValue, RGB2Value 'Add 1st and 2nd RGB longs shr RGBValue, #1 'Divide by 2 (get average of two longs) [s]RGB2Table movd RGB2HUB, HUBPointer 'Prepare self modifying code that[/s] [s]nop 'will write RGB long to HUB RAM[/s] RGB2HUB wrlong RGBValue, HUBPointer 'Write RGB data to [B]HUB[/B] RAM add HUBPointer, #4 'Point to next HUB RAM long address djnz PixelCounter, #DecimateLoop 'If PixelCounter not zero then repeat @ DecimateLoop ForeverLoop jmp #ForeverLoop PseudoIna long %00000000_00101010_00010101_00101010 NextCOG byte 2 COGSync long $1FFF FIFOReadPin long |< 7 PixelCounter long 200 COGPointer long $100 RGBValue long $0000 RGB2Value long $0000Lanternfisch: You need COGPointer as kuroenko showed (that is what I meant above !, not the comment.... I didn't see the comment, because it doesn't get compiled!)
I am at work when I read this so will fix my code when I get home. Thanks for finding my mistakes. Obvious when I look at it with a clear head and no distractions.
The Propellor is quite a shift from my previous coal-fired processor assembler experience (Z80, 6502) 100 years ago.