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-rw-r--r--firmware/microblaze/apps/txrx_uhd.c120
-rw-r--r--firmware/microblaze/lib/banal.c18
-rw-r--r--firmware/microblaze/lib/banal.h3
-rw-r--r--firmware/microblaze/lib/memory_map.h4
-rw-r--r--firmware/microblaze/lib/u2_init.c4
-rw-r--r--fpga/usrp2/vrt/vita_rx_control.v24
-rw-r--r--host/lib/usrp/usrp2/dsp_impl.cpp3
-rw-r--r--host/lib/usrp/usrp2/fw_common.h14
-rw-r--r--host/lib/usrp/usrp2/io_impl.cpp22
-rw-r--r--host/lib/usrp/usrp2/mboard_impl.cpp59
-rw-r--r--host/lib/usrp/usrp2/usrp2_regs.hpp21
11 files changed, 83 insertions, 209 deletions
diff --git a/firmware/microblaze/apps/txrx_uhd.c b/firmware/microblaze/apps/txrx_uhd.c
index 8ff3b8c58..d5b400e0c 100644
--- a/firmware/microblaze/apps/txrx_uhd.c
+++ b/firmware/microblaze/apps/txrx_uhd.c
@@ -126,14 +126,7 @@ dbsm_t dsp_rx_sm; // the state machine
// The mac address of the host we're sending to.
eth_mac_addr_t host_mac_addr;
-//controls continuous streaming...
-static bool auto_reload_command = false;
-static size_t streaming_items_per_frame = 0;
-static int streaming_frame_count = 0;
-#define FRAMES_PER_CMD 2
-
static void setup_network(void);
-static void setup_vrt(void);
// ----------------------------------------------------------------
// the fast-path setup global variables
@@ -154,9 +147,6 @@ void handle_udp_data_packet(
struct socket_address src, struct socket_address dst,
unsigned char *payload, int payload_len
){
- //store the 2nd word as the following:
- streaming_items_per_frame = ((uint32_t *)payload)[1];
-
//its a tiny payload, load the fast-path variables
fp_mac_addr_src = *ethernet_mac_addr();
arp_cache_lookup_mac(&src.addr, &fp_mac_addr_dst);
@@ -177,23 +167,12 @@ void handle_udp_data_packet(
//setup network and vrt
setup_network();
- setup_vrt();
// kick off the state machine
dbsm_start(&dsp_rx_sm);
}
-static void inline issue_stream_command(size_t nsamps, bool now, bool chain, uint32_t secs, uint32_t ticks, bool start){
- //printf("Stream cmd: nsamps %d, now %d, chain %d, secs %u, ticks %u\n", (int)nsamps, now, chain, secs, ticks);
- sr_rx_ctrl->cmd = MK_RX_CMD(nsamps, now, chain);
-
- if (start) dbsm_start(&dsp_rx_sm);
-
- sr_rx_ctrl->time_secs = secs;
- sr_rx_ctrl->time_ticks = ticks; // enqueue command
-}
-
#define OTW_GPIO_BANK_TO_NUM(bank) \
(((bank) == USRP2_DIR_RX)? (GPIO_RX_BANK) : (GPIO_TX_BANK))
@@ -304,72 +283,6 @@ void handle_udp_ctrl_packet(
break;
/*******************************************************************
- * Streaming
- ******************************************************************/
- case USRP2_CTRL_ID_SEND_STREAM_COMMAND_FOR_ME_BRO:{
-
- //issue two commands and set the auto-reload flag
- if (ctrl_data_in->data.stream_cmd.continuous){
- printf("Setting up continuous streaming...\n");
- printf("items per frame: %d\n", (int)streaming_items_per_frame);
- hal_set_leds(LED_A, LEDS_SW);
- auto_reload_command = true;
- streaming_frame_count = FRAMES_PER_CMD;
-
- issue_stream_command(
- streaming_items_per_frame * FRAMES_PER_CMD,
- (ctrl_data_in->data.stream_cmd.now == 0)? false : true, //now
- true, //chain
- ctrl_data_in->data.stream_cmd.secs,
- ctrl_data_in->data.stream_cmd.ticks,
- true //start
- );
-
- issue_stream_command(
- streaming_items_per_frame * FRAMES_PER_CMD,
- true, //now
- true, //chain
- 0, 0, //time does not matter
- false
- );
-
- }
-
- //issue regular stream commands (split commands if too large)
- else{
- hal_set_leds(0, LEDS_SW);
- auto_reload_command = false;
- size_t num_samps = ctrl_data_in->data.stream_cmd.num_samps;
- if (num_samps == 0) num_samps = 1; //FIXME hack, zero is used when stopping continuous streaming but it somehow makes it inifinite
-
- bool chain = num_samps > MAX_SAMPLES_PER_CMD;
- issue_stream_command(
- (chain)? streaming_items_per_frame : num_samps, //nsamps
- (ctrl_data_in->data.stream_cmd.now == 0)? false : true, //now
- (ctrl_data_in->data.stream_cmd.chain == 0)? chain : true, //chain
- ctrl_data_in->data.stream_cmd.secs,
- ctrl_data_in->data.stream_cmd.ticks,
- false
- );
-
- //handle rest of the samples that did not fit into one cmd
- while(chain){
- num_samps -= MAX_SAMPLES_PER_CMD;
- chain = num_samps > MAX_SAMPLES_PER_CMD;
- issue_stream_command(
- (chain)? streaming_items_per_frame : num_samps, //nsamps
- true, //now
- (ctrl_data_in->data.stream_cmd.chain == 0)? chain : true, //chain
- 0, 0, //time does not matter
- false
- );
- }
- }
- ctrl_data_out.id = USRP2_CTRL_ID_GOT_THAT_STREAM_COMMAND_DUDE;
- break;
- }
-
- /*******************************************************************
* Peek and Poke Register
******************************************************************/
case USRP2_CTRL_ID_POKE_THIS_REGISTER_FOR_ME_BRO:
@@ -463,25 +376,6 @@ eth_pkt_inspector(dbsm_t *sm, int bufno)
//------------------------------------------------------------------
-static bool vrt_has_trailer(void){
- return USRP2_HOST_RX_VRT_TRAILER_WORDS32 > 0;
-}
-
-static void setup_vrt(void){
- // setup RX DSP regs
- sr_rx_ctrl->nsamples_per_pkt = streaming_items_per_frame;
- sr_rx_ctrl->nchannels = 1;
- sr_rx_ctrl->clear_overrun = 1; // reset
- sr_rx_ctrl->vrt_header = (0
- | VRTH_PT_IF_DATA_WITH_SID
- | (vrt_has_trailer()? VRTH_HAS_TRAILER : 0)
- | VRTH_TSI_OTHER
- | VRTH_TSF_SAMPLE_CNT
- );
- sr_rx_ctrl->vrt_stream_id = 0;
- sr_rx_ctrl->vrt_trailer = 0;
-}
-
/*
* 1's complement sum for IP and UDP headers
*
@@ -554,13 +448,6 @@ fw_sets_seqno_inspector(dbsm_t *sm, int buf_this) // returns false
buff->control_word = MK_RX_CTRL_WORD(vrt_len);
buff->vrt_header[0] = (buff->vrt_header[0] & ~VRTH_PKT_SIZE_MASK) | (vrt_len & VRTH_PKT_SIZE_MASK);
- // queue up another rx command when required
- if (auto_reload_command && --streaming_frame_count == 0){
- streaming_frame_count = FRAMES_PER_CMD;
- sr_rx_ctrl->time_secs = 0;
- sr_rx_ctrl->time_ticks = 0; //enqueue last command
- }
-
return false; // we didn't handle the packet
}
@@ -662,13 +549,6 @@ hal_gpio_set_sels(GPIO_RX_BANK, "aaaaaaaaaaaaaaaa");
// FIXME Figure out how to handle this robustly.
// Any buffers that are emptying should be allowed to drain...
- if (auto_reload_command){
- // restart_streaming();
- // FIXME report error
- }
- else {
- // FIXME report error
- }
putchar('O');
}
}
diff --git a/firmware/microblaze/lib/banal.c b/firmware/microblaze/lib/banal.c
index 23f5f3b8a..42937957f 100644
--- a/firmware/microblaze/lib/banal.c
+++ b/firmware/microblaze/lib/banal.c
@@ -29,21 +29,3 @@ get_uint64(const unsigned char *s)
{
return (((uint64_t)get_uint32(s)) << 32) | get_uint32(s+4);
}
-
-uint32_t
-divide_uint64(uint64_t dividend, uint32_t divisor)
-{
- uint32_t result = 0;
- uint64_t dividend_ = 0;
- for(int i = 31; i >= 0; i--){
- //approximate the divisor with the ith result bit set
- uint64_t tmp = dividend_;
- tmp += (uint64_t)divisor << i;
- //set the ith result bit if the approximation is less
- if (tmp <= dividend){
- dividend_ = tmp;
- result |= 1 << i;
- }
- }
- return result;
-}
diff --git a/firmware/microblaze/lib/banal.h b/firmware/microblaze/lib/banal.h
index 6d9420602..7b3c71a20 100644
--- a/firmware/microblaze/lib/banal.h
+++ b/firmware/microblaze/lib/banal.h
@@ -87,7 +87,4 @@ get_int64(const unsigned char *s)
void
print_ip(struct ip_addr ip);
-uint32_t
-divide_uint64(uint64_t dividend, uint32_t divisor);
-
#endif /* INCLUDED_BANAL_H */
diff --git a/firmware/microblaze/lib/memory_map.h b/firmware/microblaze/lib/memory_map.h
index fed1e5259..cdf3dd338 100644
--- a/firmware/microblaze/lib/memory_map.h
+++ b/firmware/microblaze/lib/memory_map.h
@@ -525,10 +525,6 @@ typedef struct {
volatile uint32_t pad[7]; // Make each structure 16 elements long
} sr_rx_ctrl_t;
-#define MAX_SAMPLES_PER_CMD 0x3fffffff
-#define MK_RX_CMD(nsamples, now, chain) \
- ((((now) & 0x1) << 31) | (((chain) & 0x1) << 30) | ((nsamples) & 0x3fffffff))
-
#define sr_rx_ctrl ((sr_rx_ctrl_t *) _SR_ADDR(SR_RX_CTRL))
// --- dsp rx regs ---
diff --git a/firmware/microblaze/lib/u2_init.c b/firmware/microblaze/lib/u2_init.c
index 399d834cb..40237ba87 100644
--- a/firmware/microblaze/lib/u2_init.c
+++ b/firmware/microblaze/lib/u2_init.c
@@ -50,8 +50,8 @@ u2_init(void)
hal_gpio_set_ddr(GPIO_TX_BANK, 0x0000, 0xffff);
hal_gpio_set_ddr(GPIO_RX_BANK, 0x0000, 0xffff);
- hal_gpio_write(GPIO_TX_BANK, 0x0000, 0xffff); // init s/w output value to zero
- hal_gpio_write(GPIO_RX_BANK, 0x0000, 0xffff);
+ //hal_gpio_write(GPIO_TX_BANK, 0x0000, 0xffff); // init s/w output value to zero
+ //hal_gpio_write(GPIO_RX_BANK, 0x0000, 0xffff);
dsp_rx_regs->gpio_stream_enable = 0; // I, Q LSBs come from DSP
diff --git a/fpga/usrp2/vrt/vita_rx_control.v b/fpga/usrp2/vrt/vita_rx_control.v
index 669b8299d..742dd47e0 100644
--- a/fpga/usrp2/vrt/vita_rx_control.v
+++ b/fpga/usrp2/vrt/vita_rx_control.v
@@ -31,13 +31,13 @@ module vita_rx_control
wire [63:0] rcvtime_pre;
reg [63:0] rcvtime;
- wire [29:0] numlines_pre;
- wire send_imm_pre, chain_pre;
- reg send_imm, chain;
+ wire [28:0] numlines_pre;
+ wire send_imm_pre, chain_pre, reload_pre;
+ reg send_imm, chain, reload;
wire full_ctrl, read_ctrl, empty_ctrl, write_ctrl;
reg sc_pre2;
wire [33:0] fifo_line;
- reg [29:0] lines_left;
+ reg [28:0] lines_left, lines_total;
reg [2:0] ibs_state;
wire now, early, late;
wire sample_fifo_in_rdy;
@@ -67,7 +67,7 @@ module vita_rx_control
shortfifo #(.WIDTH(96)) commandfifo
(.clk(clk),.rst(reset),.clear(clear_int),
.datain({new_command,new_time}), .write(write_ctrl&~full_ctrl), .full(full_ctrl),
- .dataout({send_imm_pre,chain_pre,numlines_pre,rcvtime_pre}),
+ .dataout({send_imm_pre,chain_pre,reload_pre,numlines_pre,rcvtime_pre}),
.read(read_ctrl), .empty(empty_ctrl),
.occupied(command_queue_len), .space() );
@@ -98,7 +98,7 @@ module vita_rx_control
.src_rdy_o(sample_fifo_src_rdy_o), .dst_rdy_i(sample_fifo_dst_rdy_i),
.space(), .occupied() );
- // Inband Signalling State Machine
+ // Inband Signallling State Machine
time_compare
time_compare (.time_now(vita_time), .trigger_time(rcvtime), .now(now), .early(early), .late(late));
@@ -111,9 +111,11 @@ module vita_rx_control
begin
ibs_state <= IBS_IDLE;
lines_left <= 0;
+ lines_total <= 0;
rcvtime <= 0;
send_imm <= 0;
chain <= 0;
+ reload <= 0;
end
else
case(ibs_state)
@@ -121,10 +123,12 @@ module vita_rx_control
if(~empty_ctrl)
begin
lines_left <= numlines_pre;
+ lines_total <= numlines_pre;
rcvtime <= rcvtime_pre;
ibs_state <= IBS_WAITING;
send_imm <= send_imm_pre;
chain <= chain_pre;
+ reload <= reload_pre;
end
IBS_WAITING :
if(go_now)
@@ -141,14 +145,21 @@ module vita_rx_control
if(lines_left == 1)
if(~chain)
ibs_state <= IBS_IDLE;
+ else if(empty_ctrl & reload)
+ begin
+ ibs_state <= IBS_RUNNING;
+ lines_left <= lines_total;
+ end
else if(empty_ctrl)
ibs_state <= IBS_BROKENCHAIN;
else
begin
lines_left <= numlines_pre;
+ lines_total <= numlines_pre;
rcvtime <= rcvtime_pre;
send_imm <= send_imm_pre;
chain <= chain_pre;
+ reload <= reload_pre;
if(numlines_pre == 0) // If we are told to stop here
ibs_state <= IBS_IDLE;
else
@@ -178,3 +189,4 @@ module vita_rx_control
{ 2'b0, overrun, chain_pre, sample_fifo_in_rdy, attempt_sample_write, sample_fifo_src_rdy_o,sample_fifo_dst_rdy_i} };
endmodule // rx_control
+
diff --git a/host/lib/usrp/usrp2/dsp_impl.cpp b/host/lib/usrp/usrp2/dsp_impl.cpp
index 84314a656..bd61ac376 100644
--- a/host/lib/usrp/usrp2/dsp_impl.cpp
+++ b/host/lib/usrp/usrp2/dsp_impl.cpp
@@ -77,9 +77,6 @@ void usrp2_impl::init_ddc_config(void){
_ddc_decim = default_decim;
_ddc_freq = 0;
update_ddc_config();
-
- //initial command that kills streaming (in case if was left on)
- issue_ddc_stream_cmd(stream_cmd_t::STREAM_MODE_STOP_CONTINUOUS);
}
void usrp2_impl::update_ddc_config(void){
diff --git a/host/lib/usrp/usrp2/fw_common.h b/host/lib/usrp/usrp2/fw_common.h
index e80001ff2..f28013cf6 100644
--- a/host/lib/usrp/usrp2/fw_common.h
+++ b/host/lib/usrp/usrp2/fw_common.h
@@ -34,7 +34,7 @@ extern "C" {
//defines the protocol version in this shared header
//increment this value when the protocol is changed
-#define USRP2_PROTO_VERSION 2
+#define USRP2_PROTO_VERSION 3
//used to differentiate control packets over data port
#define USRP2_INVALID_VRT_HEADER 0
@@ -70,9 +70,6 @@ typedef enum{
USRP2_CTRL_ID_WRITE_THESE_I2C_VALUES_BRO = 'h',
USRP2_CTRL_ID_COOL_IM_DONE_I2C_WRITE_DUDE = 'H',
- USRP2_CTRL_ID_SEND_STREAM_COMMAND_FOR_ME_BRO = '{',
- USRP2_CTRL_ID_GOT_THAT_STREAM_COMMAND_DUDE = '}',
-
USRP2_CTRL_ID_POKE_THIS_REGISTER_FOR_ME_BRO = 'p',
USRP2_CTRL_ID_OMG_POKED_REGISTER_SO_BAD_DUDE = 'P',
@@ -114,15 +111,6 @@ typedef struct{
_SINS_ uint8_t data[sizeof(_SINS_ uint32_t)];
} i2c_args;
struct {
- _SINS_ uint8_t now; //stream now?
- _SINS_ uint8_t continuous; //auto-reload commmands?
- _SINS_ uint8_t chain;
- _SINS_ uint8_t _pad[1];
- _SINS_ uint32_t secs;
- _SINS_ uint32_t ticks;
- _SINS_ uint32_t num_samps;
- } stream_cmd;
- struct {
_SINS_ uint32_t addr;
_SINS_ uint32_t data;
_SINS_ uint8_t num_bytes; //1, 2, 4
diff --git a/host/lib/usrp/usrp2/io_impl.cpp b/host/lib/usrp/usrp2/io_impl.cpp
index 367a1d9fb..a2e99c824 100644
--- a/host/lib/usrp/usrp2/io_impl.cpp
+++ b/host/lib/usrp/usrp2/io_impl.cpp
@@ -16,6 +16,7 @@
//
#include "usrp2_impl.hpp"
+#include "usrp2_regs.hpp"
#include <uhd/transport/convert_types.hpp>
#include <boost/format.hpp>
#include <boost/asio.hpp> //htonl and ntohl
@@ -39,14 +40,23 @@ void usrp2_impl::io_init(void){
_rx_copy_buff = asio::buffer("", 0);
//send a small data packet so the usrp2 knows the udp source port
- //and the maximum number of lines (32 bit words) per packet
managed_send_buffer::sptr send_buff = _data_transport->get_send_buff();
- boost::uint32_t data[2] = {
- htonl(USRP2_INVALID_VRT_HEADER),
- htonl(_max_rx_samples_per_packet)
- };
- memcpy(send_buff->cast<void*>(), data, sizeof(data));
+ boost::uint32_t data = htonl(USRP2_INVALID_VRT_HEADER);
+ memcpy(send_buff->cast<void*>(), &data, sizeof(data));
send_buff->done(sizeof(data));
+
+ //setup RX DSP regs
+ _iface->poke32(FR_RX_CTRL_NSAMPS_PER_PKT, _max_rx_samples_per_packet);
+ _iface->poke32(FR_RX_CTRL_NCHANNELS, 1);
+ _iface->poke32(FR_RX_CTRL_CLEAR_OVERRUN, 1); //reset
+ _iface->poke32(FR_RX_CTRL_VRT_HEADER, 0
+ | (0x1 << 28) //if data with stream id
+ | (0x1 << 26) //has trailer
+ | (0x3 << 22) //integer time other
+ | (0x1 << 20) //fractional time sample count
+ );
+ _iface->poke32(FR_RX_CTRL_VRT_STREAM_ID, 0);
+ _iface->poke32(FR_RX_CTRL_VRT_TRAILER, 0);
}
/***********************************************************************
diff --git a/host/lib/usrp/usrp2/mboard_impl.cpp b/host/lib/usrp/usrp2/mboard_impl.cpp
index 36bef4f25..48aeb2a62 100644
--- a/host/lib/usrp/usrp2/mboard_impl.cpp
+++ b/host/lib/usrp/usrp2/mboard_impl.cpp
@@ -119,40 +119,31 @@ void usrp2_impl::set_time_spec(const time_spec_t &time_spec, bool now){
}
void usrp2_impl::issue_ddc_stream_cmd(const stream_cmd_t &stream_cmd){
- //setup the out data
- usrp2_ctrl_data_t out_data;
- out_data.id = htonl(USRP2_CTRL_ID_SEND_STREAM_COMMAND_FOR_ME_BRO);
- out_data.data.stream_cmd.now = (stream_cmd.stream_now)? 1 : 0;
- out_data.data.stream_cmd.secs = htonl(stream_cmd.time_spec.secs);
- out_data.data.stream_cmd.ticks = htonl(stream_cmd.time_spec.get_ticks(get_master_clock_freq()));
-
- //set these to defaults, then change in the switch statement
- out_data.data.stream_cmd.continuous = 0;
- out_data.data.stream_cmd.chain = 0;
- out_data.data.stream_cmd.num_samps = htonl(stream_cmd.num_samps);
-
- //setup chain, num samps, and continuous below
- switch(stream_cmd.stream_mode){
- case stream_cmd_t::STREAM_MODE_START_CONTINUOUS:
- out_data.data.stream_cmd.continuous = 1;
- break;
-
- case stream_cmd_t::STREAM_MODE_STOP_CONTINUOUS:
- out_data.data.stream_cmd.num_samps = htonl(0);
- break;
-
- case stream_cmd_t::STREAM_MODE_NUM_SAMPS_AND_DONE:
- //all set by defaults above
- break;
-
- case stream_cmd_t::STREAM_MODE_NUM_SAMPS_AND_MORE:
- out_data.data.stream_cmd.chain = 1;
- break;
- }
-
- //send and recv
- usrp2_ctrl_data_t in_data = _iface->ctrl_send_and_recv(out_data);
- UHD_ASSERT_THROW(htonl(in_data.id) == USRP2_CTRL_ID_GOT_THAT_STREAM_COMMAND_DUDE);
+ UHD_ASSERT_THROW(stream_cmd.num_samps <= FR_RX_CTRL_MAX_SAMPS_PER_CMD);
+
+ //setup the mode to instruction flags
+ typedef boost::tuple<bool, bool, bool> inst_t;
+ static const uhd::dict<stream_cmd_t::stream_mode_t, inst_t> mode_to_inst = boost::assign::map_list_of
+ //reload, chain, samps
+ (stream_cmd_t::STREAM_MODE_START_CONTINUOUS, inst_t(true, true, false))
+ (stream_cmd_t::STREAM_MODE_STOP_CONTINUOUS, inst_t(false, false, false))
+ (stream_cmd_t::STREAM_MODE_NUM_SAMPS_AND_DONE, inst_t(false, false, true))
+ (stream_cmd_t::STREAM_MODE_NUM_SAMPS_AND_MORE, inst_t(false, true, true))
+ ;
+
+ //setup the instruction flag values
+ bool inst_reload, inst_chain, inst_samps;
+ boost::tie(inst_reload, inst_chain, inst_samps) = mode_to_inst[stream_cmd.stream_mode];
+
+ //issue the stream command
+ _iface->poke32(FR_RX_CTRL_STREAM_CMD, FR_RX_CTRL_MAKE_CMD(
+ (inst_samps)? stream_cmd.num_samps : ((inst_chain)? _max_rx_samples_per_packet : 1),
+ (stream_cmd.stream_now)? 1 : 0,
+ (inst_chain)? 1 : 0,
+ (inst_reload)? 1 : 0
+ ));
+ _iface->poke32(FR_RX_CTRL_TIME_SECS, stream_cmd.time_spec.secs);
+ _iface->poke32(FR_RX_CTRL_TIME_TICKS, stream_cmd.time_spec.get_ticks(get_master_clock_freq()));
}
/***********************************************************************
diff --git a/host/lib/usrp/usrp2/usrp2_regs.hpp b/host/lib/usrp/usrp2/usrp2_regs.hpp
index 0e2a18756..67a342217 100644
--- a/host/lib/usrp/usrp2/usrp2_regs.hpp
+++ b/host/lib/usrp/usrp2/usrp2_regs.hpp
@@ -207,4 +207,25 @@
#define FR_ATR_FULL_TXSIDE FR_ATR_BASE + 12
#define FR_ATR_FULL_RXSIDE FR_ATR_BASE + 14
+///////////////////////////////////////////////////
+// ATR Controller, Slave 11
+///////////////////////////////////////////////////
+// The following 3 are logically a single command register.
+// They are clocked into the underlying fifo when time_ticks is written.
+#define FR_RX_CTRL_STREAM_CMD _SR_ADDR(SR_RX_CTRL + 0) // {now, chain, num_samples(30)
+#define FR_RX_CTRL_TIME_SECS _SR_ADDR(SR_RX_CTRL + 1)
+#define FR_RX_CTRL_TIME_TICKS _SR_ADDR(SR_RX_CTRL + 2)
+
+#define FR_RX_CTRL_CLEAR_OVERRUN _SR_ADDR(SR_RX_CTRL + 3) // write anything to clear overrun
+#define FR_RX_CTRL_VRT_HEADER _SR_ADDR(SR_RX_CTRL + 4) // word 0 of packet. FPGA fills in packet counter
+#define FR_RX_CTRL_VRT_STREAM_ID _SR_ADDR(SR_RX_CTRL + 5) // word 1 of packet.
+#define FR_RX_CTRL_VRT_TRAILER _SR_ADDR(SR_RX_CTRL + 6)
+#define FR_RX_CTRL_NSAMPS_PER_PKT _SR_ADDR(SR_RX_CTRL + 7)
+#define FR_RX_CTRL_NCHANNELS _SR_ADDR(SR_RX_CTRL + 8) // 1 in basic case, up to 4 for vector sources
+
+//helpful macros for dealing with stream cmd
+#define FR_RX_CTRL_MAX_SAMPS_PER_CMD 0x1fffffff
+#define FR_RX_CTRL_MAKE_CMD(nsamples, now, chain, reload) \
+ ((((now) & 0x1) << 31) | (((chain) & 0x1) << 30) | (((reload) & 0x1) << 29) | ((nsamples) & 0x1fffffff))
+
#endif /* INCLUDED_USRP2_REGS_HPP */