Rasmus Althoff CT800 User manual

Manual CT800
a dedicated chess computer
(c) 2016-2017 by Rasmus Althoff
althoff@ct800. et
docume t versio : v1.32

Table of Contents
1 I itial Operatio ...................................................................................................................4
1.1 Batteries.......................................................................................................................4
1.2 Wall Power...................................................................................................................5
1.3 Overvoltage..................................................................................................................5
2 Tech ical Data.....................................................................................................................6
2.1 Hardware.....................................................................................................................6
2.2 Software.......................................................................................................................7
3 Playi g.................................................................................................................................8
3.1 User Moves..................................................................................................................8
3.2 Computer Moves.........................................................................................................9
3.2.1 Move Output..........................................................................................................9
3.2.2 Quick Replies........................................................................................................9
3.2.3 Status I formatio ...............................................................................................10
3.2.4 Resig .................................................................................................................11
3.3 Cha gi g Sides..........................................................................................................11
3.4 Ca cel Computi g.....................................................................................................11
3.5 U do...........................................................................................................................11
3.6 Redo...........................................................................................................................11
3.7 Positio Display.........................................................................................................12
3.8 Game I fo..................................................................................................................12
3.9 Display Light..............................................................................................................12
3.10 Auto-Save................................................................................................................12
4 Dialogue System...............................................................................................................13
4.1 Battery I fo.................................................................................................................13
4.2 Power-o Self Test.....................................................................................................14
4.3 Game Fi ished..........................................................................................................14
5 Me u System....................................................................................................................15
5.1 Me u Tree..................................................................................................................16
5.2 New Game.................................................................................................................16
5.3 File.............................................................................................................................17
5.3.1 Load Game.........................................................................................................17
5.3.2 Save Game.........................................................................................................17
5.3.3 Erase Game........................................................................................................17
5.3.4 Book....................................................................................................................18
5.3.5 Reset...................................................................................................................18
5.4 Positio ......................................................................................................................19
5.4.1 View Positio .......................................................................................................19
5.4.2 E ter Positio ......................................................................................................19
5.4.3 View Notatio ......................................................................................................20
5.5 Time...........................................................................................................................21
5.5.1 Time Mode..........................................................................................................21
5.5.2 Time Details........................................................................................................24
5.5.3 Soft TPM.............................................................................................................24
5.5.4 Bo i.....................................................................................................................25
5.6 Misc............................................................................................................................26
5.6.1 Colour..................................................................................................................26
5.6.2 Blur......................................................................................................................26
5.6.3 Turbo...................................................................................................................26
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5.6.4 Disp.....................................................................................................................27
5.6.5 Light....................................................................................................................27
5.6.6 Beep....................................................................................................................28
5.7 I fo.............................................................................................................................28
6 Software Update...............................................................................................................29
7 Troubleshooti g.................................................................................................................30
7.1 Power-o Self Test.....................................................................................................30
7.2 Auto-Save I fo...........................................................................................................31
7.3 Reset Diag ostics......................................................................................................31
7.4 System Crash............................................................................................................32
7.5 Ge eral Ha dli g.......................................................................................................32
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1 Initial Operation
You ca power the CT800 either usi g batteries or usi g a wall power adaptor.
1.1 Batteries
Put the mai switch o the backside to positio “1”. Place four batteries of AA type i the
battery holder, either rechargeable o es (NiMH, ickel-metal hydride) or disposable o es
(alkali e type).
The polarity must match the o e i dicated o the i side of the battery compartme t. With
wro g polarity, the CT800 will ot start up, but it will ot suffer damage.
Put the mai switch o the backside to positio “2”. The CT800 should start ow.
The expected ru i g time with 2200 mAh AA batteries is 37.5 hours at regular 168 MHz
( orm), assumi g 50% computi g time a d 50% user time. The ru i g time for o -
sta dard clocks is: 42 hours at 144 MHz (eco), 33.5 hours at 200 MHz (turbo) a d 30
hours at 240 MHz (hypercharge).
The battery voltage is mo itored to preve t damagi g NiMH rechargeable batteries by
deep discharge, see chapter 4.1. Battery I fo. Disposable batteries (alkali e type) will also
work, though they are ot eco omic i the lo g ru .
Note:
•always use ide tical batteries, i.e. of the same capacity, age a d temperature, a d
by the same ma ufacturer.
•always keep rechargeable batteries at the same chargi g state, i.e. charge them
together i the same battery charger at the same time u til they are fully charged.
•ever mix disposable batteries at differe t discharge levels.
•ever mix rechargeable a d disposable batteries.
•switch off the CT800 whe it tells you to do so, or cha ge to exter al power.
•remove empty batteries from the CT800.
•remove the batteries from the CT800 whe ot usi g it for more tha about a
mo th.
Otherwise, the battery mo itori g will ot work properly, which could damage the batteries.
The electrolyte of the batteries could leak outside, which would damage the housi g.
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1.2 Wall Power
Use a mai s-to-USB adaptor that delivers 200 mA at 5 V DC. The CT800 offers a USB
type B socket at the backside. Though it is ot strictly guara teed, most computers a d
laptops will also be suitable to deliver the ecessary power from a USB port.
Put the mai switch o the backside to positio “1” to have the CT800 ru from the
exter al power supply.
Note: ru i g o exter al power does ot recharge the i ter al batteries. Therefore, you
ca safely use exter al power without removi g the i ter al batteries.
1.3 Overvoltage
Putti g more tha 7.5 V to the CT800 will make the releva t fuse for the power source
(exter al or i ter al) melt dow . Cha gi g the fuse will require qualified perso el. There
is a suitable reserve fuse i side the CT800, type 5×20mm / 1 A fast.
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2 Technical ata
2.1 Hardware
•CPU: ARM Cortex M4 (STM32F405RG i Olimex STM32-H405).
•Speed: 168 MHz while computi g, 8 MHz while waiti g for user i put.
•Overclocki g: a 200 MHz turbo a d a 240 MHz hypercharge ca be co figured.
•ROM: 1 MB.
•RAM: 192 kB + 4 kB backup-RAM.
•Display: text display with 4×20 characters, plus a red LED, a gree LED a d a
buzzer.
•Display backlight: co trolled by software.
•I put: 4×4 matrix keypad plus o e switch for ma ual backlight activatio .
•Power i put: 4×AA rechargeable NiMH batteries or via 5 V DC wall power adapter.
No -rechargeable batteries are also suitable, though ot eco omic.
•Battery ru i g time with 2200 mAh NiMH batteries, assumi g 90% usable battery
capacity:
37.5 hours (168 MHz regular).
33.5 hours (200 MHz turbo).
30 hours (240 MHz hypercharge).
42 hours (144 MHz eco).
•Curre t co sumptio at 5 V:
18 mA while waiti g for user i put.
81 mA while computi g without overclocki g.
93 mA while computi g at 200 MHz (turbo).
107 mA while computi g at 240 MHz (hypercharge).
70 mA while computi g at 144 MHz (eco).
each plus 28 mA with active display backlight.
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2.2 Software
•Ope i g book: 20,000 differe t plies i 11,000 u ique positio s. Tra spositio s are
recog ised.
•Hash tables: 117 kB.
•Po deri g: o e.
•Maximum search depth: 20 plies full search plus 8 plies quiesce ce.
•Free ROM: The firmware image is 384 kB, out of which 248 kB are used. 95 kB are
for the ope i g book data a d 32 kB for the e dgame table.
•Free RAM: 7 kB.
•Stre gth: arou d 2100 ELO (expert class).
•Operati g system: o e / bare metal.
•Programmi g la guage: mostly C, a d some assembly.
•Compiler: GCC 6.3 Q1/2017 ARM o e-eabi.
•Author of the ARM-port: Rasmus Althoff.
•Base program: NG-Play v9.86.
•Author of NG-Play v9.86: George Georgopoulos.
•Author of the e dgame table for ki g+paw vs. ki g: Marcel va Kervi ck.
•Lice ce: GNU Ge eral Public Lice se (GPL), Versio 3 or later.
As per the GPL, those who receive the executable program (e.g. i side the chess
computer itself) have the right to also obtai the program source text, the build
scripts a d the i structio s how to i stall the executable program o the chess
computer.
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3 Playing
3.1 User Moves
You e ter moves by givi g the from-square a d the to-square of a move, followed by the
a key. The square keys cha ge their mea i g (ra k / file) depe di g o whether a ra k
or a file is expected.
For example, to start a game with e2-e4, you type E5 B2 E5 D4 a. With the first key, a
file is expected, so E5 evaluates to "E". The followi g key mea s a ra k, i this case the
seco d ra k, so B2 gives "2".
There is o differe ce betwee e teri g a piece or a paw move. So if you i stead wa t to
begi the game with Ng1-f3, you e ter G7 A1 F6 C3 a.
Taki g a piece does ot require a special markup. The CT800 k ows that the desti atio
square is occupied so that the move is automatically recog ised as capture. This holds
also for taki g a paw "e passa t".
Castli g is treated as a pure ki g move e.g. from e1 to g1. The rook positio will be
updated automatically.
Promoti g a paw mea s e teri g the from-square, the to-square a d optio ally the
promotio piece:
•Quee : A1
•Rook: B2
•Bishop: C3
•K ight: D4
If you do ot e ter a specific promotio piece, a quee will be selected automatically.
Imagi e that there is a black paw o c2 a d a white rook o d1. Black wa ts to take the
rook a d promote the paw to a k ight. The the seque ce is C3 B2 D4 A1 D4 a.
If you have made a typo before pressi g the a key a d wa t to correct it, press the r
key. You ca start over e teri g your move.
The CT800 checks whether a e tered move co forms to the chess rules a d will refuse
i valid moves.
After you have e tered a valid move, the coordi ate move otatio will automatically be
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co verted to a “pretty pri t” format. E.g. whe starti g the game with Ng1-f3, you e ter
“g1f3”, but the display will be “Ng1-f3”. Captures will have “x” i stead of “-” betwee the
squares. If a move gives check, “+” will be appe ded. Mate is de oted with “#” i stead of
“+”.
Note: the time o ly cou ts while the game scree is active. Duri g a y ki d of dialogue,
positio viewer or me u access, the time cou ti g stops.
3.2 Computer Moves
3.2.1 Move Output
After e teri g your move, the CT800 will thi k about its a swer move. While it is thi ki g,
the display i its move li e will be “...”. If you play i “time per move” mode, the CT800
occasio ally may take additio al time whe “soft time per move” is co figured. The the
thi ki g display will cha ge to “.oO”. Whe the CT800 has computed its move, it will
replace the “...” by its computed move i “pretty pri t” format.
3.2.2 Quick Replies
I time modes other tha a alysis mode (see chapter 5.5.1. Time Mode), the CT800 may
reply much faster tha what you would expect from the time co figuratio . These quick
replies shall save thi ki g time for the CT800 a d keep oppo e ts from usi g the CT800's
thi ki g time (po deri g) whe the move is obvious or forced. Quick replies are triggered if
a y of the followi g co ditio s is true:
•the CT800 has a ope i g book move available, a d the ope i g book is active
(see chapter 5.3.4. Book).
•the CT800 has o ly o e legal move.
•the CT800 has o ly o e move that avoids bei g mated i the ext move.
•the CT800 ca mate.
•the CT800 ca ot avoid bei g mated (will choose some ra dom move).
•the CT800 has a obvious move i the middlegame.
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The defi itio of a obvious move is that all of the followi g co ditio s are true:
•the shallow sorti g pre-search of 3 plies depth shows a score drop of at least 2
paw s betwee the best a d seco d best move.
•the best move has bee part of the pri cipal variatio i the previous tur , or the
result is withi a ± 0.5 paw wi dow of the evaluatio from the tur before. If either
of these two pieces of i formatio is available, quick replies will ot be triggered by
a obvious move. This may happe e.g. right after the e d of the ope i g book,
after taki g back moves or after switchi g sides.
The ± 0.5 paw wi dow covers two aspects:
•If the CT800 seems to be wi i g a piece out of owhere, the CT800 will assume
that a sacrifice may be goi g o , a d that eeds serious calculatio . That is why the
CT800 will ot capture quickly if the oppo e t simply loses a piece by eglect.
•If the seemi gly obvious move still makes the CT800 sta d much worse tha
expected from the previous tur , the maybe the CT800 had already see
somethi g better, e.g. a mati g attack.
I depe de tly from forced or obvious moves, the CT800 also takes a look at how much
thi ki g time it has left for its move. If it has already used up more tha 55% of the
allocated move time whe starti g the ext search depth iteratio , it will drop the ext
depth iteratio because it would ot be able to complete it a yway.
3.2.3 Status Information
Towards the upper right cor er of the display, there ca be additio al otifiers whe the
CT800 a ou ces its move:
•“b” : The CT800 took this move from its ope i g book.
•“+” : The CT800 thi ks it is up by at least 0.5 paw s.
•“-” : The CT800 thi ks it is dow by at least 0.5 paw s:
•“++” : The CT800 thi ks it is up by at least 3.0 paw s, which is a decisive
adva tage.
•“--” : The CT800 thi ks it is dow by at least 3.0 paw s, so it is likely to loose the
game.
•“+m” : The CT800 sees a forced mate a d will wi .
•“-m” : The CT800 sees that it ca be mated.
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