Zilog S3F80P5 - Manual (Page 7)

UM026602-0515 P R E L I M I N A R Y Target Power
S3 Flash In-System Programmer
User Manual
4
RESET. Input; an active Low signal that resets the S3 Flash MCU.
SDAT. Serial data; bidirectional signal.
SCLK. Serial clock; input for the S3 Flash MCU.
V
DD
, V
SS
. Power.
Target Power
During programming, downloading and debugging, power to the S3 target can be pro-
vided by the development board through the USB connector or an external power source.
Alternatively, the S3 Flash ISP can be configured to supply power to the S3 target. Please
note however, that the S3 Flash ISP is only capable of providing up to 100mA of current at
3.3V. If the target board requires more current, be sure to connect the USB cable and/ or
use an external power source.
It is safe to apply additional power when the S3 Flash ISP is connected to a target board
because the S3 Flash ISP device features a built-in diode on the V
DD
line.
Ground
Ensure a good ground connection between the S3 Flash MCU and the connector to avoid
injection of noise into the SDAT, the SCLK, and especially the TEST/V
PP
traces during
code download and debugging.
Connecting to the Target Board
Observe the following procedure to safely connect the S3 Flash In-System Programmer
(ISP) to the target board.
1. Connect the Mini-B connector of the USB cable to the S3 Flash ISP.
2. Connect the Type A connector of the same USB cable to the host PC. The yellow LED
of the S3 Flash ISP will illuminate.
3. If you are following this procedure for the first time, ensure that the USB driver has
been properly installed; see Appendix A. Installing the S3 Flash ISP Driver on page 6.
4. Connect the 10-pin ribbon cable to the S3 Flash ISP as shown in Figure 3.