view venus/src/usb/usb_domain_bctl.v @ 98:3ab69117b09f default tip

minnie/doc/Design-spec: finished in the first pass
author Mychaela Falconia <falcon@freecalypso.org>
date Sun, 01 Oct 2023 08:17:05 +0000
parents 9309cebe07b8
children
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/*
 * This module encapsulates the USB domain circuit for boot control.
 */

module usb_domain_bctl (GND, P_3V3, ChanB_RTS, ChanB_DTR, CTL1_out, CTL2_out);

input GND, P_3V3;
input ChanB_RTS, ChanB_DTR;
output CTL1_out, CTL2_out;

/* pull-up resistors on FT2232D outputs */

resistor ChanB_RTS_pullup (ChanB_RTS, P_3V3);
resistor ChanB_DTR_pullup (ChanB_DTR, P_3V3);

/* open drain buffers */

logic_ic_common od_buf_common ( .Vcc(P_3V3),
				.GND(GND)
	);

capacitor od_buf_bypass_cap (P_3V3, GND);

buffer_slot_od buf_CTL1 (.A(ChanB_RTS), .Y(CTL1_out));
buffer_slot_od buf_CTL2 (.A(ChanB_DTR), .Y(CTL2_out));

endmodule