--- /dev/null
+Here are my current guesses about the role of various connector lines
+inside the [[MultiMode II|MultiMode].
+
+DB-25 line descriptions
+=======================
+
+========== ======================================= =======================================
+DB-25 line Role To
+========== ======================================= =======================================
+1 Stepper A Main 3
+2 Stepper B Main 20
+3 +5 Volts Main 7 (also 1,2,18,19 through 20 Ohms)
+4 Auxiliary D (role?) Jumper 2
+5 HV to piezo (-Y) Piezo 5
+6 NCAFMJM pin 2 (role?) Main 8
+7 HV to piezo (-X) Piezo 9
+8 Piezo/head chassis ground Peizo 1; Head 13; Jumper 8
+9 -15 Volts Main 26
+10 Analog 2 (gain select) Main 17, Jumper 6
+11 Vertical cantilever deflection Main 15
+12 Green loop (photodiode ground?) Main 27
+13 BB2107 pin 5 (2+) though R (role?) Main 9
+14 Manual switch mode AFM/LFM (+5 Volts?) Switch 10
+15 Stepper C Main 4
+16 Stepper D Main 21
+17 Head Gnd? Head 1
+18 HV to piezo (+Y) Piezo 4
+19 Main board ground Main 5
+20 HV to piezo (+X) Piezo 8
+21 Horizontal deflection Main 33
+22 HV to piezo (+Z) Piezo 6
+23 NCAFMJM pin 3 (role?) Main 25
+24 +15 Volts Main 10
+25 AD620 pin 2 (in -) through R (role?) Main 31
+========== ======================================= =======================================
+
+Main board line descriptions
+============================
+
+========= ========================================================= ===============================
+Main line Role To
+========= ========================================================= ===============================
+1 Stepper C, from DS3658N pin 6 Stepper Black
+2 Stepper A, from DS3658N pin 1 Stepper Brown
+3 Stepper A? in DB-25 1
+4 Stepper B? in DB-25 15
+5 Main board ground (black loop) DB-25 19
+6 Manual stepper switch direction Switch Purple
+7 +5 Volts DB-25 3
+8 NCAFMJM pin 2 DB-25 6
+9 through R to BBOPA2107 pin 5 (+2) DB-25 13
+10 +15 Volts DB-25 24, Head 5 though 10 Ohms
+11 Photodiode D Head 11
+12 Photodiode A Head 9
+13 DG403 pin 10
+14 internal plane, but not ground loop?
+15 Vertical cantilever deflection 620 pin 6 (out) DB-25 11
+16 DG403DJ pin 6 DB-25 11
+17 Gain select DG 419pin 6 (through R) DB-25 10
+18 Stepper D, from DS3658N pin 8 Stepper Orange
+19 Stepper B, from DS3658N pin 3 Stepper Yellow
+20 Stepper C? in DB-25 2
+21 Stepper D? in DB-25 16
+22 AD827(far) pin 7 (out) (Tapping-piezo voltage) Head 15, tipholder 6
+23 Green loop Head 14
+24 Manual stepper switch enable Switch grey
+25 NCAFMJM pin 3 DB-25 23
+26 -15 Volts DB-25 9, Head 7 through 10 Ohms
+27 Green loop DB-25 12
+28 Photodiode ground (green loop) Head 2
+29 Photodiode C Head 10
+30 Photodiode B Head 8
+31 AD620 pin 2 (in -) through R DB-25 25
+32 BBOPA2107 pin 1(out1) through R(total photodiode)
+33 DG403 pins 1 and 3 (drains from 1)(Horizontal deflection) DB-25 21
+34
+========= ========================================================= ===============================
+
+Chip list
+=========
+(following the [[!ltio multimode_main_board_chips.jpg]] numbering)
+
+===== ================ ====================================================== =====================================================
+Index Chip Description Role
+===== ================ ====================================================== =====================================================
+1 DS3658N Current sink. Stepper motor current sink
+2 H7555IBA CMOS timer. Manual stepper motor control clock
+3 "NCAFMJM" ? Stepper motor
+4 AD827JN Dual op amp. Far side amplifies tapping piezo signal (out Main 22)
+5 Scratched out ? Stepper motor?
+6 Scratched out ? Stepper motor?
+7 AD534KD Difference multiplier (X1-X2)(Y1-Y2)/(10V)+Z2. Photo-diode?
+8 AD734BQ Identical to AD534, but with control over denominator. Photo-diode?
+9 SG531P 25.0000 M 25 MHz crystal oscillator. Photo-diode?
+10 BBOPA 2107AU Dual op amp. Photo-diode?
+11 DG419DJ CMOS analog switch. Photo-diode?
+12 DG403DJ CMOS analog switch. Photo-diode?
+13 AD534JD Identical to AD534KD, but with slightly more error. Photo-diode?
+14 AD637JD RMS-to-DC converter. Photo-diode?
+15 AD620AR Instrument amplifier. Photo-diode?
+16 BBOPA 2604AU Op amp. Photo-diode?
+17 DG411DJ Quad CMOS analog switch ?
+===== ================ ====================================================== =====================================================
+
+Main board wiring
+=================
+
+Vertical deflection (Main line 15) comes from pins 6 and 8 (shorted
+together) of the DG403 switch. Pin 6 drains pin 5 and pin 8 drains
+pin 9 when the switch is turned on. I'm not sure what pin 5 is
+attached to. Pin 9 is connected (through a resistor) to the output
+(pin 12) of AD534a.
+
+Manual switch connector line descriptions
+=========================================
+
+Line Color Role To
+1 Orange Laser LED ?
+2 White-red STM mode LED DB-25 17
+3 Green Mode TM Main 13
+4 Blue Mode STM 120 Ohms to DB-25 17
+5 Purple Stepper direction Main 6
+6 White-brown Stepper switch +5 Volts Main 7
+7 White Laser LED? DB-25 17
+8 Yellow Laser LED?
+9 White-brown STM mode LED 160 ohms to DB-25 17??
+10 Red Mode AFM/LFM, +5 Volts DB-25 14
+11 Grey Stepper enable Main 24
+12 Black Stepper switch Gnd Main 5
+
+
+AFM head micro-D 15 connector line descriptions
+===============================================
+
+outside female from top-left: 8 7 6 5 4 3 2 1/15 14 13 12 11 10 9
+
+inside male (on board) from bottom-right: 8 7 ... 1/9 10 11 ... 15 blank
+
+==== ============================================================= ========================
+Line Role To
+==== ============================================================= ========================
+1 Laser Ground DB-25 17
+2 Photodiode ground Main 28
+3 +5 Volts Laser Power no main, no DB-25 ??
+4
+5 +15 Volts DB-25 24 through 10 Ohms
+6 STM current? Jumper 1, tipholder 2
+7 -15 Volts DB-25 9 through 10 Ohms
+8 Photodiode B Main 30
+9 Photodiode A Main 12
+10 Photodiode C Main 29
+11 Photodiode D Main 11
+12 AFM tip Jumper 3, tipholder 4
+13 Chassis ground DB-25 8, Jumper 8
+14 Tapping-piezo ground (main board shorts to photodiode ground) Main 23, tipholder 5
+15 Tapping-piezo voltage Main 22, tipholder 6
+==== ============================================================= ========================
+
+(see, e.g. Glenair_) for Micro-D-Subminiature connector descriptions.)
+
+.. _Glenair: http://www.glenair.com/micro-d/index.htm
+
+AFM head to tipholder line descriptions
+=======================================
+
+Labeled looking down on tipholder along laser, with Multimode LCD at
+bottom from top-left: 1 2 3/4 5 6
+
+==== ===================== =================================================================
+Line Role To
+==== ===================== =================================================================
+1 +12 Volts ?
+2 STM current? AFM connector 4
+3 -12 Volts ?
+4 AFM tip? AFM connector 12
+5 Ground AFM connector 14, main 23, main board shorts to photodiode ground
+6 Tapping-piezo voltage AFM connector 15, main 22
+==== ===================== =================================================================
+
+On our tapping-in-air tipholders, removing the connector-pad plate
+shows lines 1-4 are not connected to anything. Lines 5 and 6 have
+wires heading over towards the piezo, as you would expect. On our
+tapping-in-fluid tipholders, the pad is not removable, but the only
+wires leaving the pad area connect to the oscillating piezo region, so
+both tipholders have identical interfaces to the head, with 5/6
+providing piezo oscillation and 1-4 as non-contacts.
+
+Since both tapping mode pins are shorted through the head to the main
+board, but not to the DB-25 connector to the NanoScope, we assume the
+tapping oscillation is being generated on the MulitMode main board
+itself.
+
+Piezo connector line descriptions
+=================================
+
+outside male from top-left: 1 2 3 4 5/6 7 8 9
+
+inside male (on board) from top-left: same + blank
+
+DB-25 labeled HV: 5,7,18,20,22
+
+==== ======== =================
+Line Role To
+==== ======== =================
+1 Ground DB-25 8, Jumper 8
+2 no db
+3 no db
+4 +Y piezo DB-25 18
+5 -Y piezo DB-25 5
+6 +Z piezo DB-25 22
+7 Piezo cap Jumper 7
+8 +X piezo DB-25 20
+9 -X piezo DB-25 7
+==== ======== =================
+
+Jumper pin descriptions
+=======================
+
+inside male from top-left: 1 2 3 4 5 6 7 8
+
+Roles from MultiMode manual, 14-9
+
+=== =========== =========================
+Pin Role To
+=== =========== =========================
+1 STM current Head 6
+2 Auxiliary D DB-25 4
+3 AFM tip Head 12
+4 Analog 2 DB-25 10
+5 Gain Select Main 17
+6 Analog 2 DB-25 10
+7 Piezo Cap Piezo 7
+8 Ground DB-25 8, Piezo 1, Head 13
+=== =========== =========================
+
+LCD connector descriptions
+==========================
+
+inside male from top-left: 1 2 3 4 5 / 6 7 8 9 10
+
+=== =========================== =================
+Pin Role To
+=== =========================== =================
+1 Manual switch AFM/LFM, +5 V DB-25 14
+2 Total photodiode voltage Main 32
+3 -15 Volts Main 26
+4 +15 Volts Main 10
+5 Manual switch STM mode Switch 9
+6 Head Gnd? DB-25 17
+7 Main 16
+8 Green loop Main 27, DB-25 12
+9 Main 13
+10 Horizontal deflection Main 33
+=== =========================== =================
+
+
+LCD board
+=========
+
+inside male from top-left: 1 2 3 4 5 / 6 7 8 9 10
+
+=== ======================== =========================
+Pin Role To
+=== ======================== =========================
+1 +5 V Big regulator
+2 Total photodiode voltage
+3 -15 Volts
+4 +15 Volts
+5 Manual switch STM mode
+6 Head Gnd?
+7 Main 16
+8 Ground Black loop
+9
+10 Horizontal deflection top center BBOPA though R
+=== ======================== =========================
+
+[[!tag tags/hardware]]