> > How many bytes could I send approximately in one interrupt by using a > > serial cable (com port on PC and joystick on MSX)? > > Don't connect the COM port to anything other than RS232, because the COM port > signals are at 12V.
You can convert the voltages using some chips and condensators. The timing is the actual problem. > JoyNet can be used between a PC parallel port and an MSX joystick port. You > can find the schematics on Laurens' site. If you want a simple low-cost > cable, please use JoyNet. Its speed is good enough for multiplayer games or > telnet, but it's a bit slow for transferring files. Also depends on the protocol used, and if it's optimized ofcourse. > > Just by making a little program on MSX that keeps checking for data... > > On an MSX2 I got about 3.5 kilobyte per second, on turbo R about 14 kilobyte > per second. (At the other side of the cable was the same PC in both cases.) > > As you can see, the bottleneck is the CPU, not the cable. The joystick port > is not very convenient for I/O, because you have to switch PSG registers a > lot (between reg 14 and 15). Also, there is no buffering (RS232 has FIFOs and > you can send bytes to the interface instead of single bits). Yes. I think it's easiest to use an RS232. The Sunrise one only costs about 80 guilders, and you can get mine (perfect state, also Sunrise) for less. ~Grauw -- For info, see http://www.stack.nl/~wynke/MSX/listinfo.html
