摘要 |
To reduce waste and scrap of automotive electronic computer-type control apparatus constructed in hybrid technology on a substrate, due to malfunction, incorrect programming or desired change in data stored in the memory chip of a read-only memory (ROM) also applied in hybrid technology to the substrate, the substrate has a socket for a standard plug-insertable ROM or programmable ROM hard-wired connected thereto, the memory chip being enabled by application of a voltage applied to a circuit having a severable bridge (12) so that, upon severance of the bridge, the logic voltage applied to the chip will be of the "disable" value, permitting insertion of a standard ROM or PROM (16) into the additional socket (9) for supply of replacement data, the additional socket being hard-wired to a terminal (15) having an "enable" reference potential thereon. Preferably, isolating or decoupling resistors (3) are included in the address lines between the microprocessor (1) and the memory chip (5) to decouple the memory chip address input from the address inputs (8) of the additional socket and hence the additional memory (16 ).
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