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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3.2.4 Resi n
The CT800 resig s if it is dow by more tha 9.5 paw s. It will do so usi g a dialogue box.
You ca either co firm the capitulatio with a or decli e it with r if you wa t to play
u til mate. I the latter case, the CT800 will ot resig a ymore i this game.
3.3 Changing Sides
If it is your tur a d you wa t the computer to co ti ue i your place, press the ~ key.
The computer will start thi ki g immediately.
Note: cha gi g sides is o ly possible with the time co trol modes “time per move”,
“a alysis” or “mate-i ”. If the game is bei g played i “tour ame t” or “game-i ” mode, a
dialogue box will offer to switch to “time per move”.
3.4 Cancel Computing
If the CT800 is thi ki g, you ca i terrupt the calculatio s a d force it to move immediately
by pressi g the ~ key.
3.5 Undo
If it is your tur a d you wa t to u do a move, press the 3 key. You ca o ly u do a full
move, ot a si gle ply. Possible time booki gs will be u do e, too. If there is othi g to
u do, the red “error” LED will bli k.
3.6 Redo
If it is your tur a d you wa t to redo a move you have u do e usi g the “u do”
fu ctio ality, press the 4 key. You ca o ly redo a full move, ot a si gle ply. Possible
time booki gs will be redo e, too. If there is othi g to redo, the red “error” LED will bli k.
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3.7 Position isplay
If it is your tur a d you wa t to check the positio o the board, you ca press the key.
A positio display will show up where the upper a d lower half of the board will be
displayed side by side.
Pressi g that key agai will flip the board. Pressi g it o ce more will display the material
list which shows the rough differe ce i material, cou ted i paw s. The paw scori g is
quee =9, rook=5, bishop=3, k ight=3 a d paw =1.
Press the a or the r key to switch back to the game scree .
3.8 Game Info
If it is your tur , you ca press the i key to ope a dialogue box with some game
i formatio . You will get the evaluatio of the positio i paw s a d the computi g depth i
plies. I case that the selective search is deeper tha the brute force base, the depth
display will be “x / y”. x i dicated the brute force base, a d y the selective depth.
If a pri cipal variatio is available, pressi g the a key will display it. The output format,
however, will ot be the “pretty pri t” format, but the from-to otatio .
3.9 isplay Light
You ca switch o the display backlight at a y time usi g the ☼ key. This will override a y
co figured light setti gs for 30 seco ds.
3.10 Auto-Save
After every move, the game will be saved automatically u less you have a ma ually saved
game, which blocks the auto-save. I case of power loss or immediate system shutdow
due to faili g batteries, you will be able to retrieve the last game status after the ext
power-o via the me u system, see chapter 5.3.1. Load Game.
The CT800 is able to keep a saved game for about o e week without bei g powered.
For power-o auto-save diag ostics, see also chapter 7.2. Auto-Save I fo.
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4 ialogue System
At various poi ts, i teractive dialogue boxes ca appear. The captio of the box will tell
you what it is about, a d at the bottom, the available optio s appear, selectable by
differe t keys.
You co firm i fo dialogue boxes by pressi g a (“EN”). A selectio dialogue ca also be
decli ed by pressi g r (“CL”). Sometimes, also the positio key may be offered
(“POS”).
4.1 Battery Info
The most importa t u solicited dialogue box refers to the battery status. The i put voltage
is mo itored, a d if the batteries become weak (at 1.06 V per cell), you will get the “weak
batteries” war i g.
It is recomme ded to cha ge the batteries at this poi t. Assumi g 50% user time a d 50%
computi g time, the batteries will fail i about 20-30 mi utes.
The display backlight a d the overclocked turbo mode will be disabled, but otherwise, the
system will ru as usual. This war i g, however, does ot work duri g other dialogues or
i me u mode.
If the voltage drops further (to 1.00 V per cell), keepi g the system ru i g for much lo ger
would possibly damage the batteries by deep discharge. The CT800 will issue a “faili g
batteries” war i g to i form you that it has to be switched off as to preve t damagi g the
batteries. This war i g works at all times.
After co firmi g the “faili g batteries” war i g or after a timeout of 15 mi utes, the display
will be switched off. The red LED will flash to remi d you of actually switchi g off the
system. If the beeper is ot co figured to “off” (see chapter 5.6.6. Beep), there will be o e
click per seco d.
There is e ough margi to actual deep discharge that the batteries will ot suffer damage
as lo g as you switch off the CT800 whe it requests so. However, letti g it ru lo g-
lasti gly i flash/beep shutdow mode will fi ally damage the batteries.
Whe starti g a ew game, the CT800 checks the batteries. The CPU freque cy is
ramped up for maximum curre t draw. This load stress test takes about a seco d.
Upo switchi g o the device, the startup scree also i cludes ru i g the battery test.
However, whe starti g a other ew game, there is a waiti g scree with a progress bar.
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The acceptable mi imum battery voltage (1.10 V per cell) is higher tha duri g the game.
If the batteries are u likely to make it throughout the ew game, the CT800 will require
cha gi g the batteries beforeha d as to avoid this hassle duri g the game.
Note: the auto-save feature (see chapter 3.10. Auto-Save) allows to cha ge the batteries
without losi g the o goi g game.
4.2 Power-on Self Test
The CT800 checks itself after power-o , a d if problems are fou d, a dialogue box will
i form you. See chapter 7. Troubleshooti g for details.
4.3 Game Finished
Whe the game is fi ished, a dialogue box shows up telli g the reaso . You ca just
co firm it by a, or you ca press the positio key. The latter will show you the fi al
positio . Repeated will flip the positio a d display the list of material. After co firmi g
with a or r , the full game otatio will appear. You ca scroll through the otatio with
3 a d 4 . Quit the otatio listi g with a or r , a d the CT800 will offer a ew game.
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5 Menu System
The co figuratio of the CT800 is do e via the me u system. You ca access it by
pressi g the ≡ key if it is your tur . The mai me u will ope . It is orga ised as a me u
tree, a d you ca select the differe t optio s by pressi g the correspo di g square keys. It
is the file letter that cou ts. So if a optio is offered as “a:”, pressi g the A1 key will
select it.
I side a selectio optio , use the 3 a d 4 keys to cha ge the optio value.
For getti g up o e level, you ca press the a or the r key. If you are at the top level
already, that will leave the me u system.
If you wa t to leave the me u, press the ≡ key agai . This does ot o ly work at the top
level, but from a ywhere withi the me u system.
I case you leave the me u system a d have cha ged the co figuratio , a dialogue box
will appear aski g whether the cha ges should be saved, or whether you wa t this
co figuratio just to be active for the o goi g game.
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5.1 Menu Tree
Here is a overview o the whole me u structure, starti g at the mai me u:
a: new game
b: file
a: load
b: save
c: erase
d: book
e: reset
c: position
a: view position
b: enter position
c: view notation
d: time
a: mode
b: details
c: soft TPM
d: boni
a: ischer delay
b: player bonus
c: player factor
e: misc
a: colour
b: blur
c: turbo
d: disp
e: light
f: beep
f: info
5.2 New Game
Ope s a co firmatio dialogue box, a d if you co firm, a ew game will start as per the
saved co figuratio setti gs.
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5.3 File
This me u part co tai s the load / save features, co trols the ope i g book a d offers a
device reset.
5.3.1 Load Game
Loads the curre tly saved game from the backup memory. This part of the memory is
buffered agai st loss of power for up to o e week. There is o ly e ough space for exactly
o e saved game.
If the previous game has bee i terrupted due to loss of power a d power has retur ed,
you ca use this optio to retrieve a d co ti ue the game si ce the auto-save feature has
stored the game automatically. See also chapter 5.3.2. Save Game.
5.3.2 Save Game
Save the curre t game. This will disable the auto-save feature because a ma ually saved
game has priority. See also chapter 5.3.3. Erase Game. If you do ot have a ma ually
saved game, the auto-save will save the game after each ply.
Si ce the file operatio s do ot use flash-memory, but battery buffered RAM, freque t
write operatio s do ot cause wear effects. There is o risk for lo g-term damage.
5.3.3 Erase Game
Deletes the curre tly saved game, o matter whether it is a auto-save or ma ual o e. As
a side effect, this will e able auto-save agai because after erasure, there is o ma ually
saved game that would block the auto-save.
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5.3.4 Book
Allows to tur the ope i g book off or o . With active ope i g book, the first few moves
will be played i sta tly, choosi g ra domly amo g the stored moves. This leads to more
variety i the games a d saves time i games with time co trols.
Note: i the i itial positio , the first white ply will be a book move eve whe the book is
tur ed off. This is rooted i the time ma ageme t which does ot i clude this first white
ply.
5.3.5 Reset
Resets the CT800 to factory setti gs a d erases a y saved game. Afterwards, the CT800
will restart.
The factory setti gs are as follows:
•Book: o .
•Time co trol mode: time per move.
•Time co trol details: 10 seco ds per move.
•Fischer delay: off.
•Player bo us: 15 seco ds.
•Player factor: ×1.
•Mate search depth: 4 moves.
•Colour: CT800 starts as black.
•Blur: off ( o blurred evaluatio ).
•Turbo: off ( o overclocki g).
•Disp: co trast is 50%.
•Light: automatic.
•Beep: o (keyboard click a d computer sou ds).
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5.4 Position
Here you ca view the curre t board positio or e ter a ew o e, as well as display the
game otatio of the curre t game.
5.4.1 View Position
Works just like the positio key (see chapter 3.7. Positio Display). It shows the curre t
board positio with upper a d lower half of the board bei g displayed side by side.
Pressi g flips the board, a d pressi g it o ce more displays the list of material.
You ca quit this positio viewer by pressi g a or r . If you press the ≡ key, you will
leave the positio viewer a d the me u system altogether.
5.4.2 Enter Position
Allows you to e ter a positio of your choice. You will be guided through the differe t
pieces step by step. First the white pieces i the order of ki g, quee s, rooks, bishops,
k ights a d paw s, a d the the black pieces i the same order.
Use a to co firm the piece squares for the curre t piece type a d move o to the ext
o e. If you wa t to e ter more tha o e piece of the same type, just e ter the ext square
without pressi g a i betwee .
You ca delete the last square of the curre t piece type by pressi g r .
If you e ter a piece o a square that is already occupied by a other e tered piece, that
other piece will be overwritte sile tly, with the exceptio of ki gs. Si ce a positio without
ki gs would be illegal, the ki gs' positio s will be retai ed. If you try to overwrite a ki g's
positio whe e teri g the opposite ki g's positio , there will be a war i g dialogue box
because o e of these two pieces ca be discarded safely.
For movi g back a d forth through the pieces types, use 3 a d 4 .
Duri g e teri g, the CT800 keeps track of how ma y promoted pieces have bee e tered.
E.g. if you e ter three white rooks, the o e of them must be a promoted piece. This
mea s that you ca o ly e ter up to seve white paw s. This works also the other way
arou d: if you have already e tered eight white paw s, you ca ot e ter more tha two
white rooks.
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If it is possible to e ter at least o e more piece of the curre t piece type, the last character
of the e ter li e will be a comma. Otherwise, this will cha ge to a dot. Si ce there ca o ly
be o e ki g of each colour, there will always be a dot after e teri g its positio .
The CT800 will check the validity of the e tered positio ; e.g. a positio is ot allowed
whe it has a ki g bei g i check, but the other side is to move.
After you have e tered the pieces, the CT800 asks whose tur it is, white's or black's.
Based o that i formatio , the CT800 determi es whether there are pote tial “e passa t”
squares. If so, it allows for e teri g up to o e “e passa t” square, which is verified a d
accepted or rejected. Just pressi g the a key without e teri g a “e passa t” square
selects o “e passa t” square. If the positio does ot allow a y “e passa t” squares,
this step will be skipped.
If castli g might be possible, the CT800 will ask for clarificatio o the castli g rights;
otherwise, this step will be skipped.
Fi ally, the positio viewer allows to check the e tered positio . If you fi d a mistake a d
decli e the followi g dialogue box, you will start at the positio of the white ki g, but all of
the e tered items are already listed. So you are ot forced to e ter everythi g agai . Just
scroll though the piece types usi g 3 a d 4 a d correct o ly the erro eous items.
Note: due to memory co strai ts, e tered positio s may ot allow for more tha 140
possible moves, 42 captures or 32 ways of givi g check. This is more tha e ough for a y
eve early realistic game situatio .
Note: the ope i g book works also for e tered positio s, providi g that the castli g rights
match. However, the special mi or piece evaluatio a d the draw avoidi g algorithm will
ot work. If you wa t to have the same game behaviour as i ormal play, do ot use the
positio editor a d i stead, e ter the moves ply by ply. See chapter 5.6.1 Colour for details
o how to do this.
5.4.3 View Notation
You ca scroll through the otatio of the o goi g game by usi g 3 a d 4 . You ca
quit this otatio viewer by pressi g a or r . If you press the ≡ key, you will leave the
otatio viewer a d the me u system altogether.
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