Commodore 116
Additional pictures. Note that loading the page could take a while...
(pictures copyright by M.A.Grundke)
 |
serial number: DA4 8142
... meaning it's #8142 from approx. 100.000 (?) |
 |
ASSY 250413 (with shielding) overview:
interesting to see is that almost the whole of the mainboard is covered by shielding (except for voltage regulator, fuse and some other parts on the machine's right) - the other 264's boards are not shielded, except for TED (and TED only) in the Plus/4, and (in the C16) a little cardboard with thin aluminium layer that does not deserve that designation. In the middle, you can see the latch which is
used to cool down TED, and uses the whole shielding as a heat-spreader (see the close-up futher below) |
 |
ASSY 250413 (with shielding removed) overview:
to start with an interesting fact: all the boards used in the 264-series are unique and especially designed for just one model. So is this one - it's neither like that of the C16, nor of Plus/4 or C232. In fact it looks like a higher integrated and shrinked version of the Plus/4 board, something Commodore Japan Ltd. seemed to be specialized on. Things that C116 and Plus/4 have in common are their RF-modulator and its output on the
machine's left side, as well as their cheap, flat foil keyboard-connection cable (if you've ever repaired one in a Sinclair, you know what I mean). So much for the similarities. Different are all the devices' locations on the board, as well as the board's size (the C116's is smaller than C16 and Plus/4/ C232 boards). In detail: right from the RF-modulator, below the keyboard connector, you can find the MOS 6529B (U106), and,
further right, TED (U1) with the CPU (U2) beneath it. Again right are the PLA (U101, beneath cassette- and serial-ports in the board's rear) and the two ROMs (TED BASIC at U3 and TED KERNAL at U4). Just below the ROMs are the two pieces of 16Kx4 RAM (U6,U5). All chips left of these are TTL ICs (seven 74xx) |
 |
board silkscreening, part 1:
NO.251244 REV.B PCB
hi-pric P37 B |
 |
board silkscreening, part 2:
PCB ASSY NO 250413 |
 |
| The MOS 8501R1 (or MOS 7501, if in HMOS-1 process) is code-compatible with its NMOS-produced ancestor, the MOS 6502. However, the different hardware in general (especially TED and the 264 memory map) made it difficult to port applications, such as games or disk tools, from another 6502-compatible machines such as VC-20 or C64 (although porting true BASIC 2.0 applications to BASIC 3.5 wasn't so difficult) |
 |
| 16 KBytes (2 pcs. 16Kx4, in this case Texas Instruments TMS4416-15NL) are enough for gaming and a little BASIC. But when it comes to more, not to mention professional work, both the machine's bad keyboard and the amount of RAM limit its capabilities (well, at least memory can be expanded to 64 KBytes - but the terrible keyboard remains..) |
 |
| MOS 8360R2 'TED' (or MOS 7360, if in HMOS-1 process) makes the 264-series' sound and graphics. It cannot create sprites, making it quite useless for most types of games, but it can do the more flexible shapes instead. But the name TED ('text editing device') implies that gaming was not a priority when the 264-series was conceived. Interesting is, that in C116 and Plus/4, TED is passively cooled by a metal tongue - only in the C16, it is not. See below for how this cooling works here, in the C116 (part of it are the traces of cooling paste you can see in the picture).
Also interesting is TED's production date, week 36, year 1986, when the 264-series was already sort-of dead (i.e. the remaining machines were on a sell-out). I guess that TED was just a replacement part here, and the machine itself was indeed built in 1984. What the hell does that 'S' mean?? |
 |
| Close-up on the shielding that covers a great deal of the C116's board. Note the little tongue (middle), which is part of it. It is used to spread the heat emitted by TED across the whole shielding plate (yes, it's all a large heat-spreader!). Additionally, a drop of cooling paste was used (at least in this machine) for better contact. In comparison to the TED-shielding in the Plus/4, the shielding and cooling tongue are of less conductive material than the copper tongue used there. But on the other hand, it can spread the heat to a much bigger surface. Thus, it should be equally effective.
Note again that in the C16, nothing is done in order to cool down TED |
 |
| These are the two ROMs of the C116, 318006-01 (TED BASIC) and 318004-04 (TED KERNAL Rev.4). KERNAL also contains the character generator and TEDMON, a machine code monitor. BASIC 3.5 is a great improvement, compared to the C64's BASIC 2.0, and some ways similar to the C128's BASIC 7.0 (and the ill-fated BASIC 3.6, which only existed in the Commodore LCD prototype). The improvements included support for high resolution graphics (i.e. 320x200 pixels) and the other TED features (shapes, sound),
as well as many disk commands (similar to BASIC 4.0 used in the late PETs). Unlike the Plus/4 (C264) and C232/ CV364, the C116 and C16 don't have option ROM sockets (e.g. for TriMicro 3-plus-1 software) - but who would dare to use it with this keyboard, anyway? |
 |
| MOS 6529B SPI ('Single Port Interface') is part of the 264-series I/O-management, providing one 8-bit I/O port (i.e. eight I/O lines), mainly used for keyboard I/O. Where C16 and C116 have only one 6529B, the Plus/4 has two of them and, additionally, a MOS 8551/ Synertek 6551 ACIA. Reason is the Plus/4's user-port, and a its (incomplete) implementation of RS232-compatibility. Although being specified for 3 MHz (thus the 'B'), the MOS 6529B is not clocked by normal means, just accessed |
 |
| The MOS 251641-02 PLA ('Programmable Logic Array') is also part of the I/O-subsystem of the 264-series and is thus found in all of them. As the name implies, it provides logical equations used for address-decoding functions (to determine the memory locations a device can access via address bus, RAM or ROM, and determine read- or write access). These PLAs were found in most Commodore 8-bit machines, but because of their different functions (i.e. gate configuration) not exchangeable between different series |
 |
| The C116 from behind, allowing a view on all the ports (except for the RF-out, which is located on the machine's left). From left to right: 9V DC-in for power supply part no. 251539-03 (yes, the same power supply as the C16 uses), reset button, 6 pin DIN CBM serial IEC-bus (for printers or serial diskdrives like the CBM 1541), 8 pin mini-DIN CBM264 cassetteport (for CBM VC 1531 datasette), 50 pin female edge conn. cartridge interface (for CBM 1551 or cartridges),
2x 8 pin mini-DIN JOY1/ JOY2 (e.g. for CBM T-1341) and 8 pin DIN-41524 audio/video (for monitors like the CBM 1801 with integrated audio). As for the proprietary 264-series joystick ports, there was an adaptor available to connect standard 9 pin joysticks |
Also see the Plus/4 and C16 pages!