Gamry Reference 600+ - Notes for Figure 3-5

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Figure 3-5
Microprocessors in the Reference 600+
Notes for Figure 3-5:
• Note the lack of a ground connection between the USB bus and the Reference 600+ circuitry.
• The EasyUSB firmware is loaded into EasyUSB RAM on power-up. The USB firmware can be
updated over the USB via Instrument Manager.
• The Power PC firmware is also transferred from ROM into RAM on power-up. The Power PC
firmware also can be updated over the USB via a selection in the Reference 600+ section of the
Instrument Manager. Time-critical sections of the Power PC code are kept in the processor’s fast-
cache memory.
• The term UART refers to a Universal Asynchronous Receiver Transmitter. It converts parallel data
to a self-clocking serial bit stream. The UARTs send data at 6 Mbits/s.
• The Bus Transceiver isolates bus activity on the Controller and Potentiostat boards. Only reads and
writes to locations on these boards generate bus activity. This reduces noise pick-up.
• Unlike previous Gamry Instruments’ Potentiostats, the Reference 600+ calibration data are stored
in the instrument, not in a data file. When a Reference 600+ is moved from one computer to
another, its calibration remains valid.