/-----------------\ | TI-85 LINK info | | Port 7 | \-----------------/ by Branislav Bozgai bozgai@svf.stuba.sk 1995 Connector: ---------- _____ Jack 2.5mm stereo | | - GND (Ground) |_| |_| - W (White wire) |_| - R (Red wire) Electrical performance: ----------------------- All data are transmitted in binary form - logical '1' or '0' 1 = 5V (4.9V) 0 = 0V but TI-85 uses 'negative logic' that means: 0 (0V) = active signal 1 (5V) = not active So when you turn your calculator ON you can measure between W and GND 5V (also between R and GND 5V) that means everything is in quiet state. Programming: ------------ Sending: If you want to make some wire active: OUT(7),$E8 ; W=0, R=1 OUT(7),$D4 ; W=1, R=0 OUT(7),$FC ; W=0, R=0 To deactivate signals: OUT(7),$C0 ; W=1, R=1 In assembly (e.g. if I want to make W active): LD A,$E8 OUT (7),A You can use other numbers to out (but may cause abnormal operation, I think that I can explain how it works) but TI's system is using only those above. Note: Don't forget to out $C0 at the end of transmittion otherwise both sending and receiving calculators slow down. TI is using $FC to signalise an error. Reading: IN A,(7) AND 3 ; upper bits are not important CP 3 JR Z, Nothig_is_active ; W=1, R=1 CP 2 JR Z, R_is_active ; W=1, R=0 CP 1 JR Z, W_is_active ; W=0, R=1 CP 0 JR Z, W_and_R_are_active ; W=0, R=0 $C0 = 192 = %11000000 $D4 = 212 = %11010100 $E8 = 232 = %11101000 $FC = 252 = %11111100 All routines related to link port are in ROM page 5. In TALK I'm using ROM_send_byte and ROM_read_byte routines. ROM_send_byte is at address: $643B = LD C,A to $647C = RET Input: A - byte to send Destroys: DE, BC, HL ROM_read_byte is at address: $6559 = LD B,$08 to $65CB = JR $6603 Output: A - received byte Destroys: DE, BC, HL But I'm mot calling this routines directly because they both call function $0A87 (which is error handler I think) which cause crash. Can somebody help with that? I've modified them slightly replaced JP to JR and JP $0A87 to RET. ********************************************************************* There were questions on calc-ti about where can people get from Dan Eble's ZShell and other asm progs. So I'm running anonymous FTP server at address: ftp.svf.stuba.sk There is directory ti and there you'll find everything you want. Feel free to upload anything you want into ti/incoming. I'll move it into readable area within a week. NOTE:If you can't get connection, the server may be down so please try later (we are trying to keep it in work non-stop but we have some problems) Any comments or questions to this file mail to: bozgai@svf.stuba.sk or copy to /dev/null :) --------------------------------------------------------------------------- TI85/TI82 Link-protocol V2.0 January 1995 --------------------------------------------------------------------------- If anyone have any information about the TI92/95 linkprotocol, please send it to me so I can add it to this document. --------------------------------------------------------------------------- You use the information in this document on your own risk! Per Finander E-mail:pfimdt93@tufvan.hv.se Thanks to: Pascal Bouron (bouron@aaricia.ens-cachan.fr) for providing additional information about TI82/85 & CBL protocol TSTENBERG@ntcclu.ntc.nokia.com for the C routines and information. Mattias Lindquist (mattias.lindquist@tube.ct.se) for providing me with a graphlink. --------------------------------------------------------------------------- Old black link: The linkinterface uses 2 outputs (RTS/DTR) and 2 inputs (CTS/DSR) on the serial port to communicate with the TI85/TI82. The bits CTS/DSR can be read from port $3F8+6, bit 4 (CTS) and bit 5 (DSR). The bits RTS/DTR is controlled from port $3F8+4, bit 0 (DTR) and bit 1 (RTS). $3F8 is the port- address for COM1: (or $2F8 if COM2: is used). New gray graphlink: The new link uses the serial channel to communicate with the computer. I haven't any use for the RTS/DTR outputs except they will provide the link with power. The data is sent in 9600 baud, 1 stop bit, no parity. An interrupt routine should be used when receiving data from the link. Otherwise any activity like the smartdrive can cause loss of data when receiving data from the link. I've included 5 routines in Pascal to show how to send/receive bytes to/from the TI85/TI82. These routines are not optimized and doesn't contain any timeout check. The constant "PortAddr" contains the base-port address to the com-port. PortAddr=$3F8 if the link-interface is in COM1: or $2F8 if COM2: is used. The "InitPort" procedure must be called as fast as possible, because if CTS & DSR isn't set, then the calculator will slow down when the link is connected. A new variable have been added: "Graphlink". If "Graphlink" is true the linkprocedures will use the serial channel, otherwise the I/O- pins will be used. --------------------------------------------------------------------------- All data is sent in packages. A link-packet looks like this: ID From: $85=TI85 ($82=TI82), $05 (Computer communicating with TI85) / | $02 (Computer communicating with TI82) | $15 (Unknown - accepted by TI85. If anyone | finds out the purpuse, send me a note) | The CBL version also accepts other ID:s | | Command: $06 : Variable-header (used to initiate a variabletransmission) | | $15 : Data part (the datapart of a variable) | | $36 : Answer skip/abort | | $56 : Package received OK (used to acknowledge a package) | | $92 : No more variables to send (used to end a transmission) | | $6D : Send screendump | | Low byte | | Data word / Size of DataPart | High byte | | | Data zero or more bytes | | |-- |-- |---- |----------------- |- |- $85 $56 00 00 [DataPart:00 .. 00 Checksum: 00 00] Checksum=(Sum of all bytes in the datapart) and 65535 A transmission can look like this: a variable: ABC:REAL=3.1415... (PI) from TI85 to computer (all values in hex) ID $85=TI85 (byte, $82 for a TI82) | Command (byte): Var-header | | Packet length (word, 4+NameLength for a Var-header) | | | | | | ------Datapart------ | | | Variable length (word) | | | | Type (byte 0=Real number) | | | | | Name Length (byte) | | | | | | Name | | | | | | | Checksum,(0A+03+41+42+43) and FFFF |- |- |---- |---- |- |- |------- |---- TI85: 85 06 07 00 0A 00 00 03 41 42 43 D3 00 COMPUTER: 05 56 00 00 |- |- |---- | | No packet | Command: Received OK ID $05 = Computer <=> TI85 ($02 = Computer <=> TI82) Received OK | Command: Data part | | Packet length: 10 bytes for a REAL | | | Data (PI) |- |- |---- |---------------------------- TI85: 85 56 00 00 85 15 0A 00 00 00 FC 31 41 59 26 53 58 98 COMPUTER: 05 09 00 00 |- |---- | No packet Command: Ready to receive data part Checksum Command: No more variables | | 10 bytes data was sent |---- |- |---- TI85: 30 03 85 92 0A 00 "Done..." COMPUTER: 05 56 00 00 05 56 00 00 END |- |- Received OK Received OK If a TI82 is used instead of a TI85, the Var-header command changes: 1. The "Type" byte - TI82/TI85 have different variable types 2. The "Name length" byte - don't exists for the TI82. The name is Zero- terminated (except system variables - see "name/type data for TI82"). After a Var-header have been sent, then the calculator (or computer) waits for a "Received OK"-command and an answer. The answer can be one of the following (the computer sends, TI85 receives and answers) : 85 09 07 00 : Continue (header-datalength: 7 bytes) 85 5A 07 00 : Checksum error, send last package again The two following answers can occur if the variable already exists in memory: 85 36 01 00 02 02 00 : Variable skipped ("Skip" was pressed) 85 36 01 00 01 01 00 : Variable refused ("Exit" was pressed) 85 36 01 00 03 : Out of memory If more than one variable is send, then a "Var-header" command when the reciever (calculator or computer),have acknowledged the datapackage instead of a "No more variables"-command. --------------------------------------------------------------------------- The "Type"-byte for a TI85 can have one of the following values (hex): 00 Real 01 Cplx 02 Vectr 03 Vectr complex 04 List 05 List complex 06 Matrx 07 Matrx complex 08 Const 09 Const complex 0A Equ 0B Range 0C Strng 0D-10 GDB 11 Pict 12 Prgm 13 Range 14 PrtScreen (without Name) !! 15 ? 16 ? 17 Func (range) 18 Pol (range) 19 Param (range) 1A Difeq (range) 1B ZRCL (range) 1C ? 1D Backup (without Name) !! --------------------------------------------------------------------------- Note: The "Send screendump" command can be sent to the TI85/TI82 to download a screendump to the computer. The TI85 will send a "Received Ok"-command and the a datapackage of 1024 bytes (768 bytes for the TI82). The data- package is a copy of the memoryarea $FC00-FFFF (the screen). This works almost anytime (it's not necessary the calculator is in the LINK-menu), but it won't work when a program is running (except if the program is waiting for a key). --------------------------------------------------------------------------- The var type/name data for a TI82 : 00 :Real 01 :List 01 5D 00 00 00 00 00 00 00 = L1 01 5D 01 00 00 00 00 00 00 = L2 01 5D 02 00 00 00 00 00 00 = L3 01 5D 03 00 00 00 00 00 00 = L4 01 5D 04 00 00 00 00 00 00 = L5 02 :Matrix 02 5C 00 00 00 00 00 00 00 = MA 02 5C 01 00 00 00 00 00 00 = MB 02 5C 02 00 00 00 00 00 00 = MC 02 5C 03 00 00 00 00 00 00 = MD 02 5C 04 00 00 00 00 00 00 = ME 03 :Y-Var 03 5E 10 00 00 00 00 00 00 = Y1 03 5E 11 00 00 00 00 00 00 = Y2 03 5E 12 00 00 00 00 00 00 = Y3 03 5E 13 00 00 00 00 00 00 = Y4 03 5E 14 00 00 00 00 00 00 = Y5 03 5E 15 00 00 00 00 00 00 = Y6 03 5E 16 00 00 00 00 00 00 = Y7 03 5E 17 00 00 00 00 00 00 = Y8 03 5E 18 00 00 00 00 00 00 = Y9 03 5E 19 00 00 00 00 00 00 = Y0 03 5E 20 00 00 00 00 00 00 = Xt1 03 5E 21 00 00 00 00 00 00 = Yt1 03 5E 22 00 00 00 00 00 00 = Xt2 03 5E 23 00 00 00 00 00 00 = Yt2 03 5E 24 00 00 00 00 00 00 = Xt3 03 5E 25 00 00 00 00 00 00 = Yt3 03 5E 26 00 00 00 00 00 00 = Xt4 03 5E 27 00 00 00 00 00 00 = Yt4 03 5E 28 00 00 00 00 00 00 = Xt5 03 5E 29 00 00 00 00 00 00 = Yt5 03 5E 2A 00 00 00 00 00 00 = Xt6 03 5E 2B 00 00 00 00 00 00 = Yt6 03 5E 40 00 00 00 00 00 00 = r1 03 5E 41 00 00 00 00 00 00 = r2 03 5E 42 00 00 00 00 00 00 = r3 03 5E 43 00 00 00 00 00 00 = r4 03 5E 44 00 00 00 00 00 00 = r5 03 5E 45 00 00 00 00 00 00 = r6 03 5E 80 00 00 00 00 00 00 = Un 03 5E 81 00 00 00 00 00 00 = Vn 05 :Program 07 :Pic 07 60 00 00 00 00 00 00 00 = Pic1 07 60 01 00 00 00 00 00 00 = Pic2 07 60 02 00 00 00 00 00 00 = Pic3 07 60 03 00 00 00 00 00 00 = Pic4 07 60 04 00 00 00 00 00 00 = Pic5 07 60 05 00 00 00 00 00 00 = Pic6 08 :GDB 08 61 00 00 00 00 00 00 00 = GDB1 08 61 01 00 00 00 00 00 00 = GDB2 08 61 02 00 00 00 00 00 00 = GDB3 08 61 03 00 00 00 00 00 00 = GDB4 08 61 04 00 00 00 00 00 00 = GDB5 08 61 05 00 00 00 00 00 00 = GDB6 0B :WINDW 0B 5E 81 00 00 00 00 00 00 = Window 0C :ZSTO 0C 5E 81 00 00 00 00 00 00 = RclWindow 0D :TABLE 0D 5E 81 00 00 00 00 00 00 = TblSet 0E :PrintScreen 0F :Backup --------------------------------------------------------------------------- "Command-byte" for the TI82 C9 :Variable header for "Send(" Command General Structure : =================== ID Cd Sl Sh [Data Part] Cl Ch ID : 82 or 02 Cd : Command :(06,15,36,56,6D,92,C9) Sl : Size of the data part is: Sh : Size = $100*Sh+Sl Cl : Checksum of the data-part Ch : Checksum = $100*Ch+Cl Example : --------- 02 56 00 00 : Computer -> TI , Package receive ok , no packet 82 56 00 00 : TI -> Computer , Package receive ok , no packet 02 09 00 00 : Computer -> TI , Ready to receive , no packet 82 92 ll hh : TI -> Computer , No more variable, hhll was sent Data part : =========== -> If Cd is 06 or C9 : ---------------------- [..]=Ll Lh Ty {Name = 8 bytes} Ll: Length of the variable Lh: Length = $100*Lh+Ll Ty:Type-Byte The names are always 8 bytes: ABC = 41 42 43 00 00 00 00 00 L1 = 5D 00 00 00 00 00 00 00 Examples : ========== Transmission of PROGRAM:ABC :[A] : : : : From 82 | Command : [here 06=Variable header] | | Size of data part [here = $000B] | | | Size of the variable [here = $0009] | | | | Type [$05=Prgm] | | | | Name and 00 | | | | | | | | | |\_________________ | | |\ | | | | | | | |\ | | | \ | | | | | | | | \ Checksum | | | | | A B C | | | | \ | | | | | | | | TI82 :82 06 0B 00 09 00 05 41 42 43 00 00 00 00 00 D4 00 ___________ Computer: 02 56 00 00 Data part of the variable | Length ___________ ___|_______ | [A] CR CR CR CR CR TI82 :___________ 82 56 00 00 82 15 09 00 07 00 5C 00 3F 3F 3F 3F 3F Computer:02 09 00 00 Checksum | | TI82 :9E 01 82 92 09 00 "Done" Computer: 02 56 00 00 02 56 00 00 END --------------------------------------------------------------------------- Pascal/C procedures to communicate with the TI85/TI82 and a demo program (pascal) to show how to receive a screendump or a variable from a TI85. Note: An interruptroutine should be used when receiving data from a graphlink. The "Receive"-routine can miss data if the smartdrive uses the harddisk while receiving data (for example) ! var GraphLink:Boolean; { True : Graphlink / False : Old black link } ****** Procedure to set/reset RTS/DTR: procedure SetPort(Bits:Byte); { Input: "Bits", a byte 0 - 3, bit 0 = DTR, bit 1 = RTS } begin Port[PortAddr+4]:=Bits and 3; end; ****** Function to read CTS/DSR: function GetPort:Byte; { Returns a byte 0 - 3, bit 0 = CTS, bit 1 = DSR } { if GetPort returns 0, then the calculator have noticed a timeout } var P:Byte; begin P:=(Port[PortAddr+6] and 48) div 16; if P<>(Port[PortAddr+6] and 48) div 16 then P:=(Port[PortAddr+6] and 48) div 16; GetPort:=P; { if KeyPressed then HALT(1); } { Add the line above if you don't add a timeout-check somewhere else. } { The program will probably hang in "GetPort" when the calculator } { causes a Timeout } end; ****** To send a byte to the TI85/TI82: const Bits:array[0..7] of Byte=(1,2,4,8,16,32,64,128); procedure Send(V:Byte); var Q:Byte; begin if GraphLink then begin Q:=Port[PortAddr+5]; while (Q and $40)=0 do Q:=Port[PortAddr+5]; Port[PortAddr]:=V; end else begin Q:=0; repeat if GetPort=3 then begin if (V and Bits[Q])=0 then begin SetPort(1); while ((GetPort and 2)=2) do ; SetPort(3); while ((GetPort and 2)=0) do ; end else begin SetPort(2); while ((GetPort and 1)=1) do ; SetPort(3); while ((GetPort and 1)=0) do ; end; Inc(Q); end; until Q=8; end; end; ****** To recieve a byte from the TI85/TI82: function Receive:Byte; var N,V,P:Byte; begin if GraphLink then begin P:=Port[PortAddr+5]; while (P and 1)=0 do P:=Port[PortAddr+5]; Receive:=Port[PortAddr]; end else begin N:=0; V:=0; repeat P:=GetPort; if P<>3 then begin if P=1 then begin SetPort(1); V:=V or Bits[N]; end; if P=2 then begin SetPort(2); end; while ((GetPort and (3-P))=0) do ; SetPort(3); while ((GetPort and P)=0) do ; Inc(N); if N=8 then begin Receive:=V; Exit; end; end; until false; end; end; ****** Initiates the com-port (MUST be called before anything else) procedure InitPort; var P:Byte; begin Port[PortAddr+4]:=3; { Set 9600 baud 1 stopbit No parity. Needed for the graphlink } Port[PortAddr+3]:=3+128; Port[PortAddr]:=$0C; Port[PortAddr+1]:=$00; Port[PortAddr+3]:=3; SetPort(3); { Clear receive register } P:=Port[PortAddr+5]; while (P and 1)>0 do begin P:=Port[PortAddr]; Delay(1); P:=Port[PortAddr+5]; end; end; ****** C routines /* ============================ */ typedef unsigned char uchar; typedef unsigned int uint; uint port = 0x3f8; /* = COM1, 0x2f8 for COM2 */ /* ============================ */ void setport(uchar bits) { outportb(port + 4, bits & 3); /* simple enuf to write inline code */ } /* ============================ */ uchar getport(void) { uchar b; b = inportb(port + 6) / 16 & 3; /* if (kbhit()) exit(1); */ return b; } /* ============================ */ void send(uchar b) { uchar bits; for (bits = 1; bits <= 8; bits++) { if (b & 1) outportb(port + 4,2); else outportb(port + 4,1); while (getport() != 0); outportb(port + 4,3); while (getport() != 3); b >>= 1; } } /* ============================ */ uchar recvbyt(void) { uchar curbit = 1; uchar byt = 0, bits, x; for (bits = 1; bits <= 8; bits++) { while ((x = getport()) == 3); if (x == 1) { byt += curbit; outportb(port + 4,1); x = 2; } else { outportb(port + 4,2); x = 1; } while ((getport() & x) == 0); outportb(port + 4,3); curbit <<= 1; } return byt; } /* ============================ */ /* init port: I've found that this is enough */ outportb(port + 4,3); *** Demo program to show how to receive vars/screendumps for the TI85 *** begin 644 link.zip M4$L#!!0````(`$^(*2!)\6"M/V\H2 M_X[$_S"B2'&*H;;S:`AUI3:4%!T.!,BA5%4^;.P-\<&QH_4:&J'^[V=G[?4C M<1*J>Z[NM038.X^=F9W?[.PR9^$#(S,8THA?>,'CR>[.[LX+G-)9"(K&0XBF MX3/@CWB/(PI\2L$7[(+%H6[,:`2_4&X2,DD;GG=:1_"J1\KUPOF">0]3#@/* MX,P+2."*%_/XN+5!;G='V!)!GY'Y5.\Q+HUWPB#BNSO(\MGC49I2_(FP1-B9AXRKR;K@3`D[22@_ M]87NY93GD+DIY6^=T]D\H^!<*67@.5R$25$RHTS#:AR81F::8B?.(^6PPFX) M]N-EYKZK]V>Y/5[`Z0-E)4T7-'C@4ST9ZDVI\QC%L_1S(/S\Y+HL%?^6NR,# MBUF1NA.&/B7!";S`D,54C$@&S`-X!V?$CW#LRG=A[(M998(DR_0";^4#`Y4O M,JDH?\>H^`TWP]MWI\.;;L(-65;!+>5HGB97$EW&11+SGP?SF'=A#\?W="`P M%C0PX!`:.HP]+EYM$!J3#U-\B"E2[6/ZX`72053]0[E_T!QU;=0')'"A@?/0 MP#TIF7\6!P[WP@"M9Y2XT$/#;S/#)XH._<3PKEJF%[BA/&9!M,96H2BW56A$ MA4+(FRA-8KY$WM`188&$F4-\)_8)#QE,R1.%(.2>B)R8@WLS&L8\M2M+ZH$R MJ!R'KJV58]$>R2@T.W5PO2J5G%RQYD,_U!%P-& MHTCX(QW^^NEBJ)GUA/X"0ILJ0Q3(.!3N"Z%%&(,;!C4.Q"W$X=#!G(E2U>_9\'S_&9.PO1%B#!_`"V$L-W(/GBN"G]4CJM\1?,%E?'+T2O# M5Z1*.;N\,*W124Y]GGH^!>U:KM5^TZC;A@CK%J$2:=2U[Q0-'<6`5]A@%.09 MG5/"\V_E1Q)YNU'I1\ZGW4EK$<(_KD=H\09^\:C:HE)JZ4E#H"G\H6ZK;EMU M#$2EA%+8^"V%QAJ%ZX*V.I_U^OG,NFW^JPZ8&QU8'3P/'.UZ67V9,PZXY\.U MW2FDCWBM@A"CCD>?J$+1A(6S2AQE=?F&.M1[HCEF%(PN]3N]4!Q_"TJ#UT!I MD(4+H[591%E9YAEM@]-E&4YW6]$EK$C7LKP@29G?A#?DL,W-`-N,+V'='80L M@>MET?OUV2-GM5XW:P4HJE16Y;36.!S4U^;U!I!4*1NL5810N%Q5(IR\M#N; MGDL+6N5\%>@FV,-M@=UYX'&/%JL]90EK[@HL!QVS!@3&(7 M3(AX.,=NZC*$.6$>7Z3;\[*:!JHY,*VLUBSO8?M&KY)T8$JB44UL%*U;39@7 MZ/F4,"Q?N(SB[X,7<7AZ5R\E&6DRT%J8BN4^J311F3&V8KYT"I(7$8 MI<%I/)L75RIS.7"U?:-5/RD-M-VE`<.H',C"E.8YF(;5/#`-6>4CZ&8<`/N= M%NRWVB`DY<^'0[AZ+%/-5DIM(O64<((YP7'`4"HUG*&>R:G3FF06CY!+AW+5 M]_?R1SV"19VKTJ8;'SP/WW>Q%0DA/>I5K-WNLUJ.EOS%*!2:?_ M<3_JVFE4RFN4Q>S4B^9BB24ZYZD?F"O/Q./2'@*/=%&PL>]V[6.EK#_KVA:> M\.[ZGZ#=-.`G-#L&-O5.Z(/_5:+3-7;9@W-(I]_N%C=2,F MG;X(M%J/!$$H3/.$D5_ZG\3$1Y_[Y[6B]U^)7]Q'2AZ70FR]%^%5>E,HI8.8#[R?U-?N M]>^ZV:JV\I;R'@8PJ0+IX(474,U(KQ_$GTQ4$G#,*%#RZ-Y0XOY!%_:;-+*K M0TI1SP\C*A=#C'Q)#2>1755D00/^#J M\5>)UFK_5N%-ZE'MJXR^VJ5<'0(RPQN>O6+(TX@TL1U/'6Z,#F0J)&IZ4Z9E MD:AGTV8+6=*VZ@HFQ"*Y;TGV`LQ!6;_++AK'O^7BC6@J:B>=F"HQ7^ M+8BJ<#I+T[QO4'C8G+?_(03_A_GYWRDG,H9A0)/=(^\HRXVC:D&[]KYUUL$^ M9+]QUK%[5W^:.N`0OEJ96]FYO&O+ZV<4^"NB$/JNO`9G$^)0'?='CA?6A_)_ M%_FE]:]"VX0GB'B>GV>*?4[QA/P"WU0C)3LLY.4A_GL@>*#P1'PQCY)-TZDZ M&/)NLROS_XUIZ#7S2'6[D6RMW7@VSZE61B5XF^N1,9X"L&\:$^0 All words are in LLHH format (LSB before MSB) Datalength : In the 92, Datalength's word can be different of 0 WITHOUT data and checksum. In this case, this word in an indormation: 09 87 xx xx : See 326 89 56 00 01 : 92 Receive OK but Not ready 09 09 xx xx : Ready to receive xx xx bytes Checksum : Exist if n>0. Checksum in the sum of all byte of the data. 12 Devicetype -=============- 02 : Computer > TI82 05 : Computer > TI85 09 : Computer > TI92 12 : TI92 > CBL ??? 15 : ?? > TI85 82 : TI82>TI82 or TI82>Computer 85 : TI85>TI85 or TI85>Computer 89 : TI92>TI92 or TI92>Computer 13 Command -==========- 06 : Variable header 09 : Wait Data/Continue 0D : SEND ??? 15 : Data part 36 : Refused (Not used on the 92, 92 can accept all var ?) 56 : OK 5A : CHK error , send again 68 : Test if 92 is ready (See 327) (Only found on the 92) 6D : Screen Dump 78 : Continue (See 325) (Only use by TI-92) 87 : Direct command (See 326) (Only found on the 92) 92 : End of transmission A2 : Request (See 325) (Only found on the 92) 14 Protocol -===========- Transmission of a variable from device1 to device2 1)Device1 : Var header (Name,type,length) 2)Device2 : OK 3)Device2 : WAIT 4)Device1 : OK 5)Device1 : DATAPART 6)Device2 : OK 7)Device1 : END of transmission 8)Device2 : OK If there are several variable, repeat 1) to 6) 15 Variable Header Format -=========================- 151) TI-82 ---------- Variable header: Always 11d bytes Ll Lh Ty [NAME] $100*Lh+Ll = Size of the Var Ty = Type of the variable NAME = Always 8 char, zero-terminated if length<8 (See Linkprot.txt by Per Finander for the var-code) 152) TI-85 ---------- Variable header: From 5 bytes to 12d bytes Ll Lh Ty Nl [NAME] $100*Lh+Ll = Size of the Var Ty = Type of the variable Nl = Name length (See Linkprot.txt by Per Finander for the var-code) 153) TI-92 ---------- Variable header: From 7 bytes to 23d bytes LL LH HL HH Ty Nl [NAME] HH HL LH LL= Size of the Var in Memory (Real Size +2) Ty = Type of the variable Nl = Name length (See "TI-92 LINK INTERFACE PROTOCOL" by Ben Eater and George Nachman) 16 DataPart Format -===================- 161) TI-82 ---------- Same as in Memory LL HH xx xx xx .... xx HHLL : length of the variable Example: (See Section B-11) 162) TI-85 ---------- Same as in Memory For PRGM,STRING... LL HH xx xx xx .... xx HHLL+4+length(NAME) : length of the variable in the MEM Menu For REAL,PICT,... xx xx xx Example: (See Section B-12) 163) TI-92 -------- 00 00 00 00 HH LL ....... HHLL : length of the variable.(real size) In memory, there are from HH LL to byte before chk Example: (See Section B-13) +-==========================-+ | II - BACKUP | +-==========================-+ 21) TI-82 -=========- Sorry , no informations about this. 22) TI-85 -==========- Thanks to David Boozer (adb2y@virginia.edu) TI-85 : 85 06 09 00 B1 08 1D 12 00 23 00 F7 8B 8D 02 Computer : 05 56 00 00 05 09 00 00 TI-85 : 85 15 B1 08 .. .. Part 1 .. .. Computer : 05 56 00 00 TI-85 : 85 15 12 00 .. .. Part 2 .. .. Computer : 05 56 00 00 TI-85 : 85 15 23 00 .. .. Part 3 .. .. Computer : 05 56 00 00 ( These values have been found with a ROM 3.0 after a reset.) More Detail : See B-22 23) TI- 92 -===========- Thanks to David Ellsworth (davidells@aol.com) for his help. The TI-92 Send backup if "anyone" ask it. Here is the conversation of the request send by a computer and the answers reply by 92. WHO? Byte send TRANSLATE ------------------------------------------------------------------------ Computer : 09 68 00 00 Test TI-92 : 89 56 00 00 OK Computer : 09 A2 11 00 00 00 00 00 1D 0B 6D 61 Send me (Backup) 69 6E 5C 62 61 63 6B 75 70 9F 04 main/backup TI-92 : 89 56 00 00 OK 89 06 09 00 00 04 00 00 1D 03 31 2E 33 B6 00 Backup 1kb 1.3 Computer : 09 56 00 00 OK 09 09 00 04 Ready to receive 1kb TI-92 : 89 56 00 00 OK 89 15 00 04 .. .. 1 k Of data .. .. .. CH CL 1kb of data Computer : 09 56 00 00 OK TI-92 : 89 06 09 00 00 04 00 00 1D 03 31 2E 33 B6 00 Backup 1kb 1.3 Computer : 09 56 00 00 OK 09 09 00 04 Ready to receive 1kb TI-92 : 89 56 00 00 OK 89 15 00 04 .. .. 1 k Of data .. .. .. CH CL 1kb of data Computer : 09 56 00 00 OK (* N with N>=38) TI-92 : 89 06 09 00 ll hh 00 00 1D 03 31 2E 33 B6 00 Backup hhll bytes 1.3 Computer : 09 56 00 00 OK 09 09 hh ll Ready to receive hhll TI-92 : 89 56 00 00 OK 89 15 00 04 .. hhll bytes of data .. CH CL 1kb of data Computer : 09 56 00 00 OK TI-92 : 89 92 00 00 END of Transmission Computer : 09 56 00 00 OK Rem : 1) When the computer reply 09 09 00 04, the 00 04 is not important, and can be replaced by another value, with no change. 2) I think that the 1.3 is version of the Rom. If anyone with another version as the 1.3 can confirm to me. 3) If the first reply of TI92 is 89 56 00 01, then the 92 is not ready. (See 327) +-==========================-+ | III - Special Function | +-==========================-+ 31) TI-85 -==========- 311) Screendump --------------- Computer : 05 6D 00 00 TI-85 : 85 56 00 00 85 15 00 04 .. .. Memory part , From FC00 to FFFF ... CHK Computer : 05 56 00 00 312) PrtScrn ------------ TI-85 : 85 06 03 00 00 04 14 18 00 Computer : 05 56 00 00 05 09 00 00 TI-85 : 85 56 00 00 85 15 00 04 .. .. Memory part , From FC00 to FFFF .. CHK Computer : 05 56 00 00 32) TI-92 -==========- 321) Screendump --------------- Computer : 09 6D 00 00 TI-85 : 89 56 00 00 89 15 00 0F .. .. .. .. .. .. .. .. .. .. .. .. .. .. CHK Computer : 09 56 00 00 322) Send {1,3.1} ----------------- TI-92 : 89 06 07 00 07 00 00 00 04 01 FF 0B 01 (List lenght 7 , name $FF) Computer : 09 56 00 00 09 09 00 00 TI-92 : 89 15 0B 00 02 00 00 00 20 31 20 33 2E 31 00 05 01 (02 = # of number) Computer : 09 56 00 00 TI-92 : 89 92 00 00 Computer : 09 56 00 00 323) Get a ---------- TI-92 : 89 A2 06 00 00 00 00 00 00 00 00 00 Computer : 09 56 00 00 ??????????? Can anyone help me for the end of this conversation 324) Request function --------------------- To ask a variable, backup or content to the 92. 3241) Backup : See 23 3242) Variable (Example of request : main\abd , type TEXT) Computer : 09 68 00 00 ; TI-92 ready ? TI-92 : 89 56 00 00 ; 0000= yes, 0001= no Computer : 09 A2 0E 00 00 00 00 00 00 0B 08 6D 61 69 6E ; The request 5C 61 62 64 3B 03 ; (0B = TEXT) TI-92 : 89 56 00 00 If the variable doesn't exist, the conversation stops here. TI-92 : 89 06 09 00 12 00 00 00 0B 03 61 62 64 ; Var header Computer : 09 56 00 00 09 09 00 00 TI-92 : 89 56 00 00 89 15 16 00 00 00 00 00 00 10 00 0C 20 4A 75 ; The TEXT 73 74 20 61 20 74 65 73 74 00 E0 23 05 Computer : 09 56 00 00 TI-92 : 09 92 00 00 Computer : 09 56 00 00 3242) Content (DIR) Computer : 09 68 00 00 ; See 3241 TI-92 : 89 56 00 00 ; See 3241 Computer : 09 A2 06 00 00 00 00 00 19 00 19 00 ; Order of DIR ? TI-92 : 89 56 00 00 89 06 0A 00 0E 00 00 00 53 04 main 0A 02 ; Current folder=main Repeat Computer: 09 56 00 00 ; OK 09 09 FF FF ; Waiting ... TI-92 : 89 56 00 00 89 15 18 00 00 00 00 00 m a i n 00 00 00 00 ; 31 = 31 00 01 00 00 00 C5 01 ; 01 =# of var in FOLD. Computer: 09 56 00 00 TI-92 : 89 xx 00 00 ; xx= 78 :Continue until xx= 92 ; xx= 92 :End Computer : 09 56 00 00 Each entry of the 92 is in this format : 00 00 00 00 n1 n2 n3 n4 n5 n6 n7 n8 : Name of the variable ty : Type of the variable 31 = Folder 00 = Variable is editing : No type ( Or EXPR) st : 00 = Variable OK 01 = Variable is editing ll lh hl hh : Size of the variable (or # of variable for folder) 325) Remote control of the TI-92 -------------------------------- Press ++<(>+ To control the 92, you must send a word through the link port. This word is the code of the key (page 484 of the US manual, Section B8 to B12 of the French manual) After each word send, the 92 replies by a $FF. When there is a result (after an ENTER), the 92 send this result in FF-terminated. Ex: Computer : 0031 002B 0041 000D TI -92 FF FF FF FF 412B31FF <1> <+> , the 92 reply You can do graph, factor, edit-text... To leave this mode, send the command of 326) Command 92 by link port ---------------------------- To use this mode, not necessary to put the 92 in remote mode. Format of this mode : Computer : 09 87 ll hh : Send code of the hhll key TI-92 : 89 56 00 00 : OK For example, to do <1> <+> Computer : 09 87 31 00 <1> TI-92 : 89 56 00 00 Computer : 09 87 2B 00 <+> TI-92 : 89 56 00 00 Computer : 09 87 41 00 TI-92 : 89 56 00 00 Computer : 09 87 0D 00 TI-92 : 89 56 00 00 => The result is NOT sent by the link port. You can use this mode to put the 92 in the remote mode +-==========================-+ | IV - REFERENCE DOCUMENTS | +-==========================-+ LINKPROT.TXT : V2.0 (January 1995) By Per Finander (pfimdt93@tufvan.hv.se) In this document, you can find all var-code of the TI-82 and TI-85, C and Pascal IO-routines to send or receive variables, and a demo program. TI-92 LINK INTERFACE PROTOCOL (January 1996) By Ben Eater (themouse@wam.umd.edu) and George Nachman (ltduck@wam.umd.edu) In this document, you can find all(?) var-code of the TI-92, C IO-routines to send or receive with the parallele link. Hacking the TI-85 CALCULATOR (September 1994) By David Boozer (adb2y@virginia.edu) Lot of very interesting informations about the TI85. TI-RAM.TXT V0.9 (April 1996) By Dan Eble and Rob Taylor A description of the 85'RAM TI-92 Technical Information (1996.03.29) by David Ellsworth (davidells@aol.com) ftp://users.aol.com/davidells/TI-Calc/TI-92_tech.txt Lot of very interesting informations about the TI92. --------------------------------------------------------------------------- SECTION A - Index TI-82 : Backup : 21 Checksum calcul : 11 Command byte : 13 DataPart : 161 Devicetype (02 or 82) : 12 Format of .. See this word Header format : 151 Protocol : 11,14 Transmission : 11,14 TI-85 : Backup : 22 Checksum calcul : 11 Command byte : 13 DataPart : 162 Devicetype (05 or 85) : 12 Format of ... See this word Header format : 152 Protocol : 11,14 PrtScreen : 312 ScreenDump : 311 Transmission : 11,14 Variable format : C12 VAT : C22 TI-92 : Backup : 23 Checksum calcul : 11 Command byte : 13 DataPart : 163 DataLength (Special ...) : 11 Devicetype (09 or 89) : 12 Format of ... See this word Get (command) : 323 Header format : 153 Protocol : 11,14 Remote : 325,326 Request : 324 backup : 23,3241 content : 3243 variable : 3242 ScreenDump : 321 Send (command) : 322 Transmission : 11,14 Variable format : C13 --------------------------------------------------------------------------- SECTION B : Examples ------------------------ B1 - Transmission of var ------------------------ B11) Transmission of Var with the 82 ==================================== Transmission of ABC:PROGRAM :[A] : : : : 1)TI-82 : 82 06 0B 00 09 00 05 41 42 43 00 00 00 00 00 D4 00 2)Computer : 02 56 00 00 3) 02 09 00 00 4)TI-82 : 82 56 00 00 5) 82 15 09 00 07 00 5C 00 3F 3F 3F 3F 3F 9E 01 6)Computer : 02 56 00 00 7)TI-82 : 82 92 09 00 8)Computer : 02 56 00 00 1) Var header (Length 000B) 09 00 : Size of the var , here 9 bytes 05 : Type , here PRGM 41 42 43 00 00 00 00 00 = ABC : Name D4 00 : Checksum 2) OK 3) Ready to receive 4) OK 5) Data part (Length 0009) 07 00 : Length 5C 00 : [A] 3F 3F 3F 3F 3F : CR CR CR CR CR 9E 01 : Ckecksum 6) OK 7) End of transmission, 0009h bytes was sent. 8) OK B12) Transmission of Var with the 85 ==================================== Transmission of ABC:REAL=3.1415926535898 1)TI-85 : 85 06 07 00 0A 00 00 03 41 42 43 D3 00 2)Computer : 05 56 00 00 3) 05 09 00 00 4)TI-85 : 85 56 00 00 5) 85 15 0A 00 00 00 FC 31 41 59 26 53 58 98 30 03 6)Computer : 05 56 00 00 7)TI-85 : 85 92 0A 00 8)Computer : 05 56 00 00 1) Var header (Length 0007) 0A 00 : Size of the var , here 10d bytes 00 : Type , here real 03 : Length of the name 41 42 43 = ABC : Name D3 00 : Checksum 2) OK 3) Ready to receive 4) OK 5) Data part (Length 000A) 00 00 FC 31 41 59 26 53 58 98 = 3.1415926535898 6) OK 7) End of transmission, 000Ah bytes was sent. 8) OK B13) Transmission of Var with the 92 ==================================== Transmission of a:Expr=1.23 1)TI 92 : 89 06 07 00 0C 00 00 00 00 01 61 6E 00 2)Computer : 09 56 00 00 3) 09 09 00 00 4)TI 92 : 89 56 00 00 5) 89 15 10 00 00 00 00 00 00 0A 40 00 12 30 00 00 00 00 00 23 AF 00 6)Computer : 09 56 00 00 7)TI-92 : 89 92 00 00 8)Computer : 09 56 00 00 1) Var header (Length 0007) 0C 00 00 00 : Size of the var , here 12d bytes 00 : Type , here EXPR 01 : Length of the name 61 : a : Name 6E 00 : Checksum 2) OK 3) Ready to receive 4) OK 5) Data part (Length 0010) 00 00 00 00 : ??? 00 0A : Length of var 40 .. : Var (See 163b) 6) OK 7) End of transmission, 000Ah bytes was sent. 8) OK ------------------------ B2 - Backup Informations ------------------------ B22 Information about the TI-85 Backup ====================================== In the BACKUP.85B 0000 >0007 **TI85** 0008 >000A 1A 0C 00 000B >0034 "Backup file dated 04/28/96,17:02",0 0035 >0036 ll hh : # of byte from next to Checksum 0037 >0038 09 00 : Size of the Var header 0039 >003A Size of Part 1 ($08B1) 003B Code of Backup (1D) 003C >003D Size of Part 2 (n2) 003E >003F Size of Part 3 (n3) 0040 >0041 $F7 $8B 0042 >0043 Size of Part 1 (Always? B1 08) 0044 >08F4 Part 1 08F5 >08F6 Size of Part 2 (here 12 00) (n2) 08F7 >08F6+n2 Part 2 nnnn >nnnn+1 Size of Part 3 (here 23 00) (n3) nnnn+2>nnnn+1+n3 Part 3 xxxx >xxxx+1 Checksum Description of each packet -------------------------- Part 1 :TI-85 Memory (0000 is the first byte of this packet) Size = $08B1 (2225d bytes) 0000->08B0 : Memory from : $8346 -> $8BF6 byte $8B2C : Floating point mode (3=Normal;4=Float0;5=Float1;..;F=Float11) word $8B2D : Pointer of current Floating point. (07E6) Part 2 :User Memory ($8BF7) (0000 is the first byte of this packet) 0000->nnnn-1 : Memory from $8BF7 to $8BF7-1+nnnn Part 3 :VAT (From $FA6F downto ($8BEB+1)) (Variable Allocation Table) (See C22) --------------------------------------------------------------------------- SECTION C : Other -------------------- C1 - Variable format -------------------- C11 Information about the TI-82 Variables ? ========================================= C12 Information about the TI-85 Variables ========================================= Format of some variables: PRGM : LL HH PROGRAM STRNG : LL HH STRING REAL : El Eh Rg N1 N2 N3 N4 N5 N6 N7 With EhEl : Exponent \ Rg : Range > Value =Number*10^(Exponent+100*(Range-$FC)) Ni : Number / (See the document of David Boozer for more development) C13 Information about the TI-92 Variables ========================================= Expr (00) ----------- 00 00 00 00 Th Tl [EXPR] ThTl : Size of EXPR * Data part format for an expr An expression must be read from the end to the begining. The first byte (Last) is an ID with number ID TYPE SIZE Example ------------------------------ 1F INTEGER Var. 0C 01 1F =12d >> 0C=12 01=1 byte 23 Real 12 40 00 12 30 00 00 00 00 00 23 = 1.23>> Value=*10^[-$4000-$D] Special ID ---------- 02 = r 03 = s 04 = t 05 = u 06 = v 07 = w 08 = x 09 = y 0A = z 0B = a 0C = b 0D = c 0E = d 0F = e 10 = f 11 = g 12 = h 13 = i 14 = j 15 = k 16 = l 17 = m 18 = n 19 = o 1A = p 1B = q 26 = i (i^2=-1) 8B = + 8F = * 91 = / Example : 00 00 00 00 : ?? 00 10 : size = 16 bytes 40 : exponent =(4001$ and 7FFF$)-4000$-$D=-12d 01 : signe =4001$ and $8000 =0 => (+) 12 20 00 00 00 00 00 : number=12200000000000 => 12200000000000*10^(-12) =12.2 23 : real 04 : value = 4$ \ 01 : size=1 > Integer size 1 , value 4 1F : integer / 18 : n 8F : * 8B : + => +(*(n,4),12.2) = 12.2+4*n TEXT (0B) ----------- 00 00 00 00 Th Tl Ch Cl [YOUR TEXT] 00 E0 ThTl : Size of text + 4 ChCl : Cursor Pos ! Warning ! The first byte after CR is a command and is put before ":" PIC (10) ---------- 00 00 00 00 Sh Sl Rh Rl Ch Cl [YOUR PIC] 00 DF ShSl : Size of Pic + 6 RhRl : # of row ChCl : # of col In "Normal" PIC , ShSl = RhRl*INT(((ChCl-1)/8)+1) But, the 92 don't verify this. RhRl and ChCl is only use when you display the picture. --------------- C2 - VAT format --------------- C21 Information about the TI-82 VAT ? =================================== C22 Information about the TI-85 VAT =================================== The format of each entry is : NN .. NN Ln HH LL Ty With : Ty = Type of variable HHLL = Position in RAM Ln = Length of the name NN..NN = NAME Example of VAT (without Zshell): 43 42 41 03 8C 16 12 43 42 02 8C 13 0C 41 01 8C 09 00 23 01 8C 00 12 21 C B A C B A # ! 01 8B FE 12 73 6E 41 03 8B FB 0C 74 61 74 53 79 05 8B F9 04 74 61 74 53 s n A t a t S y t a t S 78 05 8B F7 04 x xStat : LIST $8BF7 (Type $04) yStat : LIST $8BF9 (Type $04) Ans : STRNG $8BFB (Type $0C) ! : PRGM $8BFE (Type $12) # : PRGM $8C01 (Type $12) A : REAL $8C09 (Type $00) BC : STRNG $8C13 (Type $0C) ABC : PRGM $8C16 (Type $12) ! and # are used by ENTRY. C23 Information about the TI-92 VAT ? =================================== ======================================================================== !****FILE FORMATS****! ======================================================================== File format of .85G files ========================= Compiled by David Brodbeck (gull@cyberspace.com) Corrections by Magnus Hagander (mha@algonet.se) Type codes compiled by Per Finander (pfimdt93@hvdc.hv.se) The .85G files are groups of TI-85 variables. They are also the general part of all .85x files (see README.TXT for further information about this). An 85G file can contain any number of variables, as long as their total size does not exceed 64Kb. The format of the .85G file is ------------------------------ Header - 37h bytes Entry1 Entry2 .. EntryX Checksum - 2 bytes The header has the following format ----------------------------------- Offset Length Comments ====== ====== ======== 00h 08h Signature. Must be "**TI85**" 08h 03h End-Of-File marker and further signature, must be 1Ah 0Ch 00h 0Bh 2Ah Comment. This is a space- or null-padded string. It may _NOT_ contain any of the special characters on the TI-85. All normal characters are allowed, though. 35h 02h Word: Number of bytes from [next byte to EOF]-2. This variable is used to calculate the checksum of the file. Read this word. Then calculate the checksum on the n words that follows, where n is the value you just read. After that, append the checksum. Each entry has the following format ----------------------------------- Offset Length Comments ====== ====== ======== +00h 02h Word: Bytes from next byte to end of name This can be used for "fast-skipping" of the variable when seeking through the file. The word pointed to by this value is the size of the variable, and therefor the whole thing can be skipped faster. +02h 02h Word: Data length +04h 01h Byte: Type code (see table below) +05h 01h Byte: Name length +06h *h Name (plain data, no terminating null or padding spaces) *+00h 02h Word: Data length *+02h xxx Data The typecodes available are: ---------------------------- 00 Real 01 Cplx 02 Vectr 03 Vectr complex 04 List 05 List complex 06 Matrx 07 Matrx complex 08 Const 09 Const complex 0A Equ 0B Range 0C Strng 0D-10 GDB 11 Pict 12 Prgm 13 Range 14 ? 15-1B Range The checksum is calculated the following way -------------------------------------------- Sum up all the words between 37h and (filesize-2), and the value with FFFFh, and there you are. A little Pascal code snippet to show the basic idea (programmers in other languages should probably understand it too): var checksum:Word;f:file;i:Integer;b:Byte; begin seek(f,$37); checksum:=0; for i:=1 to filepos(f)-$39 do begin blockread(f,b,1); checksum:=checksum+b; end; blockwrite(f,checksum,2); end; You could also read the word at address 35h to determine how much to compute the checksum on, if you don't want to use the files size. File format of .85I files ========================= Compiled by Magnus Hagander (mha@algonet.se) The .85I files are TI-85 pictures. The pictures are 128x63 pixels with 1 bit per pixel (monochrome). They are stored as a bit-map of the screen from top-right to bottom-left, going left to right, then up to down. The format of a picture is: Offset Length Comment ====== ====== ======= 00h 02h Word: Size of picture. _ALWAYS_ F003 = 1008 (03F0h) 02h 3F0h File format of .85K files ========================= Compiled by Magnus Hagander (mha@algonet.se) The .85K files are TI-85 constants. It can contain both real and complex constants. The real constants have _EXACTLY_ the same format as real numbers (see 85N.txt) The complex constants have _EXACTLY_ the same format as complex numbers (see 85C.txt) File format of .85L files ========================= Compiled by Magnus Hagander (mha@algonet.se) The .85L files are TI-85 lists. It can contain both real and complex lists. The only difference is the identifier and the data block size. The format of a list is: Offset Length Comment ====== ====== ======= 00h 02h Word: List dimension (number of items) 02h [00h]*BS Data items. Each item is either a real number (see 85N.txt) or a complex number (see 85C.txt). BS is the block size, which is 10 for real lists and 20 for complex lists. FIle format of .85M files ========================= Compiled by Magnus Hagander (mha@algonet.se) The .85M files are TI-85 matrixes. It can contain both real and complex matrixes. The only difference is the identifier and the data block size. The format of a matrix is: Offset Length Comment ====== ====== ======= 00h 01h Byte: Vertical (Y) dimension of matrix 01h 01h Byte: Horizontal (X) dimension of matrix 02h [00h]* [01h]*BS Data items. Each item is either a real number (see 85N.txt) or a complex number (see 85C.txt). BS is the block size, which is 10 for real matrixes and 20 for complex matrixes. The values are stored in Top-Right, Top-Left, Bottom-Right, Bottom-Left order. This means that the matrix [[1,2] [3,4]] has its values stored in the order 1,2,3,4. File format of .85N files ========================= Compiled by Magnus Hagander (mha@algonet.se) The .85N files are TI-85 real values. This is the simpliest variable on the TI-85, yet sometimes one of the hardest to handle. It is also included as "sub-variable" in e.g. lists and matrixes. The format of a real value is: Offset Length Comment ====== ====== ======= 00h 01h Byte: Sign. 00h -> Positive number; 80h -> Negative number. 01h 01h Low order of 10^x value. 02h 01h High order of 10^x value. The 10^x value is calculated using: x=[01h]+256*([02h]-FCh) 03h 07h Hexa-decimal interpretion of value. The decimal point lies between Low and High nibble of [03h]. The reason that the 10^x value seems so complicated is that it should handle values between 10^999 <-> 10^-999. The "value-part" may seem confusing, but I just didn't know how to say it. A few examples will illustrate (and hopefully solve) the problem: Storage Value 00 01 02 03 04 05 06 07 08 09 10 00 01 FC 10 00 00 00 00 00 00 Pi 00 00 FC 31 41 59 26 53 58 98 -Pi 80 00 FC 31 41 59 25 53 58 98 9.99E999 00 E7 FF 99 90 00 00 00 00 00 2.5E-35 00 DD FB 25 00 00 00 00 00 00 File format of .85P files ========================= Compiled by Magnus Hagander (mha@algonet.se) The .85P files are TI-85 programs. They can appear in two different ways: Tokenized or non-tokenized. The TI-85 will tokenize a program when it's first run, and de-tokenize it as soon as the editor is opened. This is because a program will run faster when tokenized, but can only be edited when non-tokenized. The format of a tokenized program is: Offset Length Comment ====== ====== ======= 00h 02h Word: Length of program 02h Program data. Each line in the program data is terminated by character 6F. If the 6F character at the final row of the program is changed into FF, the program will be edit-locked. The format of a non-tokenized program is: Offset Length Comment ====== ====== ======= 00h 02h Word: Length of program 02h 01h Byte: Always 00h to identify non-tokenized program 03h Program data. Each line in the program is terminated by character D6, _NOT_ by CR/LF squence(s). A non-tokenized program can't be edit-locked. File format of .85S files ========================= Compiled by Magnus Hagander (mha@algonet.se) The .85S files are TI-85 strings. They can hold any characters in the TI-85's set, except for 00h. The format of a string is: Offset Length Comment ====== ====== ======= 00h 02h Word:Length of string 02h String data. File format of .85V files ========================= Compiled by Magnus Hagander (mha@algonet.se) The .85V files are TI-85 vectors. It can contain both real and complex vectors. The vectors have exactly the same format as the matrixes (see 85M.txt), but their vertical dimension (Y dimension) is locked to 1.