RAM Failure is indicated by a sequence of from 1 to 6 tones. A low-frequency tone is heard for each good RAM chip. A much lower frequency is heard for a failing RAM chip. The sequence stops with the last failing RAM chip. To restart the sequence, press the Reset pushbutton on the game PCB or set the self-test switch to off, then again to the ON position. Identify the bad RAM chip with the table below. Example: Three tones, then a tone of much lower frequency indicates failure of RAM chip R4. Tone RAM Chip Location ---------------------------- 1 D2 2 E2 3 M4 4 R4 5 N4 6 P4 ROM/PROM Failure is indicated by two columns or lines of numbers in the upper left-hand corner of the display. The number in the left column or first line indicates the failing ROM/PROM chip(s). Identify the bad ROM/PROM with the table below. The number in the right column or second line indicates the failing data bit of the failing ROM/PROM. Identify the bad bit with the second table below. If more than one bit is failing, the displayed number(s) are hexadecimal combinations of the numbers shown below. Examples: 1) If bits D2 and D3 fail, C is displayed. 2) If bits D2, D3 and D7 fail, 8C is displayed. 3) If bits D4 and D5 fail, 30 is displayed. 4) If bits D1, D3, D5 and D6 fail, 6A is displayed. Displayed No. Failing ROM/PROM ----------------------------------------------------- -05 & -06 PCB -03 & -04 PCB 0 N/P3 N/P3 K4,L4 1 N/P3 N/P3 K4,L4 2 J2 F1 F2,L1 F2,H1 3 J2 F1 F2,L1 L2,L1 4 H2 D/E1 H2,J1 H2,J1 5 H2 D/E1 H2,J1 M2,M1 6 E/F2 C1 K1,J2 J2,K1 7 E/F2 C1 K1,J2 N2,N1 Displayed No. Failing Bit ------------------------------- 1 D0 2 D1 4 D2 8 D3 10 D4 20 D5 40 D6 80 D7 RAMSEL signal failure is indicated by a BANK ERROR or PAGE SELECT ERROR message at lower middle of display.