8K RAM + 4,8 or 16K EPROM on a single card

9-04 — elektor september 1980 8K RAM + 4,8 or 16K EPROM on a single card on a Many readers have requested that the 4 k RAM card for the Elektor SC/MP system be updated. The new card presented here contains a total of 8 k of RAM, up to 16k of EPROM and can be used with either of the Elektor SC/MP systems or the Junior Computer. card Table 1 EPROM type 2708 2716 2716 2732: IC7 deleted (see text) 1k0 - 1000 ... 13FF lkl = 1400... 17FF 1k2= 1800 ... 1BFF 1k3= 1000 1FFF 1k4 = 2000 . . . 23F F 1 k 5 = 2400 . . . 27F F 1 k 6 = 2800 . . . 2B F F 1 k7 = 2000... 2F F F connect pins 9 and 5 of IC5 to inputs of N2 IC25 = IC26 = 1027 = IC28 = 3FFF input A input B address order IC25-26-27-28 IC25-27-26-28 beginning at an even page IC26-28-25-27 beginning at an odd page Al 0 Al2 Al2 All All All Table 1. This table shows the connections to the A and B inputs of 107 for the different types of EPROM. Table 2 RAM 2707 3000 ... 33FF 3400 ... 37FF 3800 3BFF 3000 3FFF connect pin 14 of IC5 to inputs ...