Apple Interactive Television Set Top Box The Apple Interactive Television, also known as the Apple Set Top Box, Model# M4120, is quite a mystery. It would appear that, with the exception of limited usage in some areas for trials and such, it was never widely distributed so little is known about it other than what can be gotten from looking at the hardware. One thing is clear though, and that is whatever network would've been put in place to support it is no longer in existence so the ITV is little more than a curiosity and is capable of doing very little. Unfortunately, I've been unable to get it to display anything at all to try and get clues as to it's operation. The ITV in my possesion shows a date of 1/27/95 for the IMS Market on it's box.

The first thing one notices about the M4120 is that, though it's casing is roughly the size of some of the pizza-box style Macintoshes, it is colored black and the only two things on the front panel are an Apple logo in the center and an on/off switch near the left edge. Behind the Apple logo is an IR port for the IR remote that would be used to control the ITV, which I don't have unfortunately. On the right side panel there is what appears to be an ADB port and along the rear panel are the master on/off switch, power connector, SCART/VCR, SCART/TV, HDI-30 SCSI, RF-out, RF-in, ethernet, serial, S-Video, and composite video/audio, as well as an expansion slot cover above the video connectors near the right side. On my ITV, the SCART connectors are hidden behind covers.

To open the ITV, you remove one screw from the rear panel and lift the top cover off. Inside, there are plenty of standard Mac parts, including the 68040 cpu, NCR 53C96 SCSI controller, Zilog Z8530 serial controller, the 3.6V PRAM battery, CUDA switch, and a 72pin SIMM socket, which appears to have a 4meg SIMM installed. There also appears to be another 4meg of RAM on the mainboard. There are 4 cable connections going to the mainboard: the PSU, the input (ADB?) port on the right side panel, the IR receiver, and the front-panel mounted on/off switch. All other ports are mounted directly to the mainboard itself. Just forward of the RAM is a mounting spot for a fan, though in this unit neither the fan nor the cable to supply power to it from the PSU are present.

Now is where the hardware get's interesting, as promised by the ports on the rear. First, near the RAM soldered to the mainboard is a socket which has a 64-pin Apple Flash SIMM installed, labled 'LC 475 GM', which contains 2048k of CMOS flash memory in the form of 8 (256k x 8) Intel E28F020 flash memory chips. Next to this is the Aztec power supply. Near the NCR and Zilog chips is the video decoder, a Philips SAA7188A, which is able to encode video data to NTSC, PAL, or S-video formats. On the other side of the mainboard is the MPEG decoding chip from C-Cube Microsystems, labled 'CL450-P160'. I've also seen mentioned that not only is MPEG decoding supported, but the hardware in the ITV is also said to support Quickdraw and Quicktime. There's also a retangular plastic frame which corresponds to the external expansion cover and which extends nearly to the front of the casing. At the forward part of this plastic frame is an expansion socket, somewhat like the PDS expansion slot of the LC-series Mac's, though this connector runs parallel to the front of the casing, not along the rear portion of the side panel. Also near the MPEG decoder is a XILINX XC4010-4 FPGA (Field Programmable Gate Array), which can be seen as a reconfigurable processor though it is unclear exactly what it's function is in this case. To the rear of the XC4010-4 is a ROM labled 'STB3 A3.1N 551AA6'.

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