Renesas M3A-0040, Инструкция по эксплуатации

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5.2 Use with other boards
The R8A66597FP corresponds to a separate bus mode and multiplex bus mode. Switch SW1 of the M3A-0040
according to MCU use. Below are notes for target board design.
5.2.1 Notes for target board design
(1) The receptacle of the target board should suit the size of this board (refer to Figure 3 and Figure 4). Make
pin arrangement the same as this board (refer to Table 1 and Table 2). Please refer to Appendix 1: the
M3A-0040 Part List and Appendix 2: the Circuit Diagram, when selecting connector and pin arrangement.
The HKP-50FD2 from Honda Tsushin Kogyo is applicable to the target board.
(2) To prevent misinsertion, please carry out stuffing the pins of target board that correspond to the #21-pin
and #22-pin of CN2 of this board. When HKP-50FD2 of Honda Tsushin Kogyo is used as a receptacle, the
GM-25K of this company is suitable for stuffing.
(3) The R8A66597FP generates a core power 1.5V from VCC 3.3V. An internal regulator makes 1.5V from
3.3V through the #19-pin and #20-pin of CN3 and outputs 1.5V to VDD pin. On the M3A-0040, 4.7uF and
0.1uF capacitors are mounted as smoothing capacitors for VDD.
(4) The interface power supply VIF is 1.8V or 3.3V.
(a) Short JP4 to “EXIOVcc” and supply 1.8V by the #25-pin and #26-pin of CN2 , when VIF is 1.8V.
(b) Short JP4 to “3.3V”, when VIF is 3.3V. In this case, power supply to VIF is the same as VCC.
(5) Use SD0-SD7 of CN2 when using split bus for DMA. SD0-SD7 can be used also as a general-purpose port.
(6) Processing for unused pin : Please refer to the R8A66597 datasheet, USB2.0 Dual Function Controller
R8A66597FP/DFP, for details.
5.2.2 VBUS control circuit
Note: When the peripheral device that connected to a USB connector is in an unusual state due to a short
circuit, or an overcurrent causes an overcurrent in VBUS, the overcurrent protection circuit of a USB
power switch IC turns on, and it turns the VBUS power supply off. But after turning off, current
around 0.4A continues flowing, and the USB power switch IC runs hot. Remove the unusual state
promptly for the sake of safety.
To start/stop supply VBUS to the peripheral device, the MCU should operate the R8A66597 to turn
on/off the VBUS output of the USB power switch IC (U2). When the USB power switch IC detects
overcurrent, it outputs a low pulse to the FLG output pin connected to the R8A66597FP, and it issues
an interrupt to MCU to notice the overcurrent state. Monitor the FLG output pin status and turn off
the VBUS output when the overcurrent state is detected by the R8A66597 control software.
Confirm that the USB device is in usual state before connecting.
(1) To supply 5V to VBUS of CN1:
(a) Apply 5V to CN4.
(b) Set JP6 to “HOST”.
(c) Output high signal from VBOUT0-pin by a R8A66597 control software.
(2) To supply 5V to VBUS of CN5
(a) Apply 5V to CN4.
(b) Output high signal from VBOUT1-pin by a R8A66597 control software.
Note: When the R8A66597 control software turn off VBUS supply from the USB power switch IC, VBUS is
not shutdown immediately but slowly because of 150uF capacitor.
5.2.3 Separate bus mode
Switch SW1 of the M3A-0040 board to “SEPA” when using as separate bus mode. Use A1-A6 of CN3 as
address bus.