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Calculators: Handheld: Commodore C110
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Size (approx): | 76mm
(max) x 132mm x 31mm (max) (w,h,d) Weight 320g including batteries |
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Power: |
9V DC, internal rechargeable battery. Accepts an adapter/charger (undefined but three in-line pin connector) through top side socket just off the middle. There is a power save function after about 15 seconds when running off batteries (portable mode) when the display switches off. | ||
| Case: | Solid and heavy calculator made from a two-piece light and dark stippled plastic case. The red plastic display filter is tilted and heavily inset to give a bright and wide angle view of the digits. Below the display is a small metallic sticker printed black with the brand and switch label. The keyboard surround is a metal panel that has a printed embossed label for the constant switch. The keys are short travel, very clicky "Klixon" type. A large panel on the back gives basic instructions | ||
| Display: | 8 digit LED with no lens with a ninth digit for power save, input overflow, overflow and low battery indicators | ||
| Features: | Standard four function with switched constant and power down display recovery. RPN logic. | ||
| Age: | 1971/2 | ||
| Manufacturer: | Commodore Business Machine, Inc. Santa Clara, California, made in the USA. Serial number 68222 | ||
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Comments:
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The very first Commodore calculator which is a branded Bowmar 901B (and also appears to be the same as the Craig 4501. Very sturdy but I cannot comment on the logic as I do not have a power supply. The original cover is black padded plastic with side and top zips and a silver printed "C" logo on the front. Unusually for an early calculator, this model appears to be very difficult to make repairs to the main board without major de-soldering work. |
| Components: | Only sketchy details due to the
difficulty of access to the main board: 1 x cpu 2 x ICS: Texas 75492N 7204A (date code week 4 of 1972), 14 pin DIL, 0.3" width 9 x one digit red LED display flat case type another 2 ICs and loads of crammed in components. |
| Boards: | The main cpu board (PM901-400/E) is attached to the Klixon keyboard assembly and front with ten screws. These are soldered together with 15 wires in a plastic block. It is therefore impossible to examine the main board without de-soldering the whole thing. The keyboard assembly has metal supports to fix to the front - no expense spared. |
| Construction: | There are two screws on the rear underneath a metallic sticker that states "Removal Voids Warranty". The rear section will then lift easily, hinging from the top. When you are inside you will see an enormous six AA-sized rechargeable battery pack, screwed to the rear. |
| Logic comments: | (CE) cancels the last entry whilst (C) clears the calculator |
| Input overflow is not suppressed, keying in a ninth digit results in an overflow which shows "E" in the far left (ninth) digit | |
| Overflow shows "[]" in the far left (ninth) digit | |
| The logic is Reverse Polish Notation: to calculate 2-3 key in (2)(+=)(3)(-=) | |
| There is switched constant function for multiply and divide only | |
| After about 15 seconds the display will show only "-" in the far left (ninth) digit to conserve power when being run from the batteries. Using the (D) key to recover the display or carry on with your calculation | |
| When the battery power is low there is an indicator: "L" in the far left (ninth) digit | |
| Cannot comment further on the logic until I get a power supply |
