DS5000(T)

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PROGRAM LOADING CONFIGURATIONS Figure 3

Table 1 summarizes the selection of the available Parallel Program Load cycles. The timing associated

with these cycles is illustrated in the electrical specs.

SERIAL BOOTSTRAP LOADER

The Serial Program Load Mode is the easiest, fastest, most reliable, and most complete method of

initially loading application software into the DS5000(T) nonvolatile RAM. Communication can be

performed over a standard asynchronous serial communications port. A typical application would use a

simple RS232C serial interface to program the DS5000(T) as a final production procedure. The hardware

configuration required for the Serial Program Load mode is illustrated in Figure 3. Port pins 2.7 and 2.6

must be either open or pulled high to avoid placing the DS5000(T) in a parallel load cycle. Although an

11.0592 MHz crystal is shown in Figure 3, a variety of crystal frequencies and loader baud rates are

supported, shown in Table 2. The serial loader is designed to operate across a 3-wire interface from a

standard UART. The receive, transmit, and ground wires are all that are necessary to establish

communication with the DS5000(T).

The Serial Bootstrap Loader implements an easy-to-use command line interface that allows an application

program in an Intel hex representation to be loaded into and read back from the device. Intel hex is the

typical format which existing 8051 cross-assemblers output. The serial loader responds to single

character commands, which are summarized below: