5140star.exe  5140 Starter Disk w/APP Selector 
pccadv11.zip  Advanced Diags (img format) Thanks, Rick!
6280655 PC Convertible Technical Reference Volume 1 Feb86
55X8817 PC Convertible Technical Reference Volume 2 Feb86

5140 Planar
   Extendable bus interface
Floppy Drive
Battery Pack
Opening the 5140
128K Memory Card
256K Memory Card
5140 Printer
Serial-Parallel Adapter
CRT Display Adapter
   CRT Video Port Pinouts
LCD
Internal Modem Port PCB
   Internal Modem Pinout
Internal Modem Board
Speech Adapter

186-049  5140 Models 2/22,  5144 Mono Display 1, 5145 Color Display 1
187-140  5140 Model 003 And Backlit LCD Option Kit
187-006 New Special Features And Functions For 5140  Models 002 / 022

DOS 3.2 or higher is required. (to support the 720K floppy)
  I have run PC DOS 7 on it. Remember, no UMB support! First, no 386. Second, it's limited to 640K max!

... Difficult... I looked at hacking ISA bus cards onto the Convertible bus. the main problem is that the address and data lines are multiplexed to get it all on the connector. You need extra logic to separate the address and data lines. I visualise a CRT slice (in this part of the world, they were cheaper
and more common than the serial/parallel slice), with the CGA logic removed, and a slot in the top of the slice with an ISA riser sticking out. If you have the upgraded power supply (originally released with the backlit LCD option, but standard in later production), you should be able to run at
least 2 ISA adapters if they aren't power hogs. Anyone got the schematic diagrams for the CGA slice?

Floppy bezel snaps on drive case. I have used an 8580 cardedge floppy with the big button- slipped right in, bezel snapped right on (now to figure out how to get 5140 to recognize 1.44!). I see no P/N or FRU on it.

From Don Hills 
   There were 2 models of floppy drive: Toshiba and Alps. The Toshiba used a metal band to drive the heads up and down, the Alps used a leadscrew. The leadscrew model could not step the heads at the full stepping rate of most PCs, so the stepping rate was set slightly slower in the BIOS. Trouble was, the metal band type drive was designed for full speed, and was very noisy when seeking at the slower speed. I wrote a small driver that loaded (and unloaded again) during boot to reset the step speed on machines with the faster drives. The drives looked identical externally, you had to look in the slot or remove them from the case to see the difference. 

From Don Hills
   I was one of those guys. If you couldn't get the "sub C" cells, the trick was to use standard C size cells and duct tape them into a pack the same shape as the original. This "naked" pack fitted in the same space as the original pack-plus-case. The battery compartment was all plastic so the new pack was well protected. Use Standard charge rate cells.

   Consider standard C cells (with tabs) instead of sub-C, if they are cheaper yet. The only reason for sub-C cells is that they will fit back in the battery case. I used standard C cells (not even solder tabs, but I am good at soldering). 

   Of course they did not fit in the case, but I wired them up in the same physical pattern to the old cells, re-using the connector and thermal fuse from the old battery. Then I placed strips of cardboard where required between the cell ends to stop them shorting, sandwiched the cells between two sheets of cardboard cut using the old case as a template, and bound the whole lot in plastic insulation tape. 

   This package looked untidy, but fit just fine in the battery compartment. Since the battery compartment is a complete plastic box in its own right, the original battery pack casing is not essential.

   Open the pack with a hammer and chisel. Clamp the pack on its side lightly in a vise with a piece of wood under it for support. Or, take a piece of scrap lumber and nail 2 short bits of 2x4 to it spaced so as to snugly hold the pack on its side. Apply chisel to the case join and tap a little harder each time until it cracks. Start at a corner and work around the pack.

   As for the power supply, as I said in an earlier post there was a US-only 110V "wall wart" that was only powerful enough to charge the battery when the system wasn't running. There was also a universal (100 to 240 volts) power "brick" (P/N 2684292) much like those used on modern laptops, that provided enough power (15 volts DC, 2.7 amps) to run the system and all accessories while charging the battery. 

   The plug is the type that has a metal outer barrel as one contact and a metal-lined hole down the middle (Center positive)  that is the other contact. Size: now pay attention here. 5.5 mm external diameter, 2.5 mm internal diameter. They also come in 2.1 mm internal diameter, so don't get 
the wrong one. 

BATTERY CHARGER (#4060): 
A 110-volt input feature designed to be used to charge the internal batteries of the system.  It does not provide sufficient power output to allow system operation while the batteries are being charged 

AUTOMOBILE POWER ADAPTER (#4065): 
Designed to charge the system battery while allowing simultaneous use of the system  unit. The adapter attaches to the system unit and plugs into the cigarette lighter outlet in a vehicle with a 12 volt negative-ground electrical system. 

   Pull the grey carrying handle forward, exposing 2 small slots in the case. Use a small screwdriver or coin to press inside the slots while lifting up on the front of the keyboard. Be careful not to damage the foil cable. Don't try unplugging it yet, just move it forwards and lay it on the extended handle. 
Note that the keyboard pivots on two small hinges at the front of the lower case. 

   Undo the 4 screws holding the diskette drives in and pull the drives out. Thumb in the diskette slot, fingers underneath is the best grip. Note that the floppy drive bezels have catches that fasten them to the drives. They are not loose! 

   Reach in through the diskette drive bays with one hand and through the opening at the rear with the other, and unclip the diskette drive plugs from the clips on the underside of the (pivoting) top cover. 

   Lift the rear of the pivoting top cover and slide it forwards until the pivot pin at the front disengages from the slot it slides in and lift the cover up and away, unplugging the foil cable to the LCD socket as you do so. 

You can now unplug the keyboard cable. 

Reassembly is the reverse of the above, just 3 tricks: 

   When screwing the diskette drives back in place, BE EXTREMELY GENTLE. The screws must not be tightened too much- you will crack the drive front plates and/or break the plastic pillars that the screws go into. THEY ARE VERY FRAGILE. (Ed. They were cracked on mine) 

From Us, the god-Emperor of Microchannel
   I found that getting the LCD unit back on was interesting. Note that the LCD swings on a "trapeeze" that has a metal pin going through it. Note the two ptllars that come up on each side of the floppy and LCD headers. Notice the arc made by the top of those pillars. See the groove? Notice that the open end is toward the front. 
   What I did- lower the LCD neck to about halfway forward. This lowers the cross-pin. Looking from the back, directly over the battery well, you can see the shaft AND the grooves. Now you can actually SEE how to position the top so the shaft will slide into the grooves. 

Back to Don
   When replacing the keyboard in its well, make sure the edge nearest the diskette drives sits on (not under) the small ledges moulded in the front plates of the diskette drives. These ledges lift the keyboard to typing position when the case is opened. If you get it wrong you may break things when you try to close the case.  The front corners of the keyboard have little pivots that mate with the front of the bottom case. I had ot push down lightly to make them "snap" in place. 

As for piggyback accessories, there were several. They were known as "slices", because they were the same profile as the back of the machine and when clipped on looked like an extension of the machine. 

A few additions to your page: 
There was no way of powering the system off completely without removing the battery. Some parts of the system, including the memory and much of the planar, were continuously powered. Being static CMOS logic, they consumed negligible power when not being clocked. The battery would hold the memory (and run the clock, there was no separate clock battery) for a couple of weeks. There was no suitable CMOS diskette controller chip so it used a standard NEC 765. This was power hungry so was actually powered off when not in use- the BIOS saved and loaded the controller's state between drive accesses. I've got a lot more somewhere, including info gleaned from conversations with the actual developers, and the full IBM Tech Ref and Hardware Maintenance Manuals. 

DESCRIPTION
       The 5140 is available in two models. The model 2 is equipped with a CMOS 80C88 microprocessor, 64Kb ROM, 256Kb RAM, an 80-column by 25-line detachable liquid crystal display, two 3.5-inch diskette drives, a 78-key keyboard, an AC adapter, and a battery pack. Also included are an Application Selector, SystemApps, Tools, Exploring the IBM PC Convertible, and Diagnostics. 
       The model 22 is the same as the model 2 with Diagnostics only. Both systems can be expanded to a maximum of 512Kb RAM via 128Kb RAM memory card features, and may include an asynchronous modem in the system unit.  The Model 003 has a backlit LCD and uses 256K memory cards.
       At the back of each system unit is an extendable bus interface.  This 72-pin connector allows any or all of the following options to attach to the base unit: Printer, Serial/Parallel Adapter, and CRT Display Adapter. Each of these features is powered from the system unit. The CRT Display Adapter operates only when the system is powered from a standard AC Adapter. A separate CRT display or television set attached via the CRT Display Adapter requires a separate AC power source. 

This card uses (16) SRM2064M-15 chips for 128K.

256K MEMORY CARD (#6030)

This card uses (8) SRM20256M-12 chips for 256K.

From Don Hills
   System memory was 640 KB max, with 256 KB as well as 128 KB cards. Any combination could be used up to 640 KB. To reach 640K with 128K cards, several people built a short ribbon cable to extend the last card's end connector to another 128KB card which they laid on top of the others under the keyboard.
   That was too tight for my liking, so I actually ran the ribbon cable through to the modem slot and put the 5th card there. 

>  Was the 640 max due to DOS limitations?
From Don Hills
   Hardware limit. Any addresses above 640 KB weren't passed to the memory cards, they were placed on the bus instead for devices like the CGA video memory.

Printer Controls
   There are three controls- A slide potentiometer on the left is for Density, left is light, right is dark. A two position switch in the middle, left is Off-Line, right is On-Line. A button is on the right for Line Feed. There is a blue lever on the left corner for clamping the guide against the roller. A paper advance wheel is on the right.

Detach Printer
   Open printer cover. Look on the left side of the printer at the front corner of the smoked plastic cover. Notice the well with the silver loop. Lift up and pivot it out. This unlatches the left side, and the right side is just a pivot. Twist off the slice, pivoting it to the right.

PRINTER CABLE (#4055): 
A cabling accessory 22 inches (0.6 meter) in length with a custom 72-pin system-type connector attached to each end. It provides the user the option of operating the Printer (#4010) immediately adjacent to (that is, physically detached from) the system unit, to provide flexibility of placement for ease-of-use and visibility.Mad Max has one of these, looks like THIS.

Port Pinouts

CGA Header
Don Hills says:
  Looking at the side of the adapter, pin 1 is at the bottom. Column A is on
the left, B on the right. Pins not listed are No Connection.
A2 Ground
A4 Blue
A5 Red
A6 Intensity
A7 Green
B1 + Vertical Sync
B3 + Horizontal Sync
B5 Ground

6 pin Header
Pin 1 at bottom, column A on left:
A1 +12v DC
A2 Missing (key)
A3 Composite Video
B1 Ground
B2 Reserved
B3 No Connection

Composite Video Pinout
Interior of RCA jack Peak-to-peak amplitude (approx 1.5v)
Exterior of RCA jack is Chassis Ground

   It allows the user the option of connecting a separate CRT display to the system. The optional 5144 PC Convertible Monochrome Display or 5145 PC Convertible Color Display may be attached via this adapter. Through the use of optional connectors or cables, the CRT Display Adapter (#4020) also allows the attachment of the IBM 4863 PCjr Color Display, IBM 5153 Color Display, or a standard television set. 

Don Hills saves my bacon by saying:
   The RCA jack is composite video out. The 18 pin header is the CGA output for the monitors (mono and colour) sold specifically for the Convertible. They came with an optional stand that held the monitor just above the system unit, in the airspace created by unclipping the LCD display after opening the unit. The connector is the same as that used on the PCjr. There is an optional 6 inch long cable with a plug to fit the header on one end and a 9 pin CGA connector on the other for connecting a standard CGA monitor.
   The 5 pin header is for an optional RF modulator, again like the PCjr one, for displaying the composite video on a stndard TV set without video in socket.

From Don Hills
   The original systems had a first generation LCD display- my first machine came with one. These were grey and low contrast. They were upgraded with a supertwist LCD (sort of green/navy blue) that had much better contrast. My first machine came bundled with this upgrade which I performed myself. I only ever saw one system with the backlit LCD. It used an electroluminescent panel rather than a fluorescent tube and diffuser. They fell out of favour because they couldn't produce as much light as a tube.
  The backlit LCD was OK in very poor light conditions, but in normal room lighting or sunlight you were much better off with the standard supertwist. I used to sit up in bed writing code (DOS device drivers in ASM, for example) with my machine. I had a small lamp mounted on the wall behind me that shone at just the right angle for good visibility. The display characters were large, and it was easy to load different fonts into the font memory until you found one you liked. 

Backlit LCD
   Backlit LCD has internal illumination, which means it can be used in low-light conditions.  Battery life is dependent on the setting of the brightness control.  The Backlit LCD works on all PC Convertible models by plugging it into the LCD assembly, in place of the current screen, and installing the new power supply.  A new power supply is packaged with the Backlit LCD Option Kit. 
   Use of the Backlit LCD with the illumination feature turned all the way up could shorten battery life to between 2.5 and 4.0hours.  The brighter the intensity the shorter the battery life.Battery life is also dependent on the application used and the amount of I/O activity. The Light Panel for the Backlit LCD has in excess of 1500 hours of illumination time. Replacement light panels (81X8536) are available as a maintenance part.

Internal Modem Port Board

IBM 5140 AP Internal Modem Connector Pinout 
Thanks, Peter! 

 I/O Pin  Signal Name               I / O 
   01     + Adress/Data Bit 0        I/O 
   02     + Adress/Data Bit 1        I/O 
   03     + Adress/Data Bit 2        I/O 
   04     + Adress/Data Bit 3        I/O 
   05     + Adress/Data Bit 4        I/O 
   06     + Adress/Data Bit 5        I/O 
   07     + Adress/Data Bit 6        I/O 
   08     + Adress/Data Bit 7        I/O 
   09     + Adress Bit 8             I 
   10     + Adress Bit 9             I 
   11     + Interupt Request 4       O 
   12     - I/O Read                I 
   13     + Reset                  I 
   14     - Data Enable             I 
   15     Ground                    GND 
   16     + Adress Latch Enable      I 
   17     Ground                    GND 
   18     + Adress Enable            I 
   19     Ground                    GND 
   20     + 12 VDC                  PWR 
   21     Ground                    GND 
   22     Ground                    GND 
   23     Ground                    GND 
   24     Ground                    GND 
   25     - 13 VDC                  PWR 
   26     Ground                    GND 
   27     - I/O Write               I 
   28     + 5 VDC                   PWR
   29     Ground                    GND 
   30     + High Z                  I 

Internal Modem Board 

IBM 5145 PC CONVERTIBLE COLOR DISPLAY MODEL 1
       The 5145 is a 13-inch (measured diagonally) color display that displays in medium resolution (320 x 200). It is designed for those customers whose application requirements will be satisfied by that resolution. It is attached to the system unit via the CRT Display Adapter (#4020).  The display stand, an AC power cord, and a signal cable that connects the 5145 to the CRT Display Adapter are provided with the 5145.  The display includes a speaker for external audio output. The 5145 will display business and graphics data in 40 x 25 character mode. In 80 x 25 character mode, the 5145 can be used for word processing and text applications. 

o   CMOS ROM has 196 stored vocabulary words
o   Supports two types of speech reproduction
    -   CVSD (Continuously Variable Slope Delta modulation)
    -   LPC (Linear Predictive Coding)
o   Microphone interface
o   Audio output

ACCESSORIES 
CARRYING CASES: Two soft-sided carrying cases are offered for the IBM PC Convertible.  The standard model (#4090) will accommodate the system unit, system-attached printer, various accessories, and supplies.  The system unit and printer can be operated from within the case.  The compact model (#4095) may be carried by hand, worn over the shoulder, or carried backpack style. This model holds the system unit in the main compartment and has an expandable pocket where the printer, accessories, and paper or a notebook may be stored. 
SUPPORTED OPTIONS: 
o   IBM 5153 Color Display 183-002 Color Display, 5153
o   IBM PCjr Adapter Cable for the IBM Color Display (#0021) 
o   IBM 4863 PCjr Color Display 
o   IBM PCjr Connector for TV (#0020) 
o   IBM Communications Adapter Cable (#2067) 
o   IBM Proprinter (#4201) 
o   IBM Graphics Printer 
o   IBM 3708 Network Control Unit 
o   IBM 3710 Communication Adapter 
o   IBM Personal Computer Printer Cable 
o   IBM 5841 Modem - 1200 bps 
       All IBM Personal Computer, IBM PCjr, IBM Personal Computer XT, IBM Personal Computer AT, or IBM Portable Personal Computer options, adapters, and devices not specifically listed above have not been tested on the IBM PC Convertible System and are not supported.