Data loss using SPWF01SA (multiples of 2kiB)

gsiebke · ‎2015-10-13

Posted on October 13, 2015 at 10:31

Hi,

i'm using the SPWF01SA with high baud rates (460k or 920k) and continuous transmission at maximum speed. From time to time (minutes for 460k, all the time for 920k), data sent via UART is not transmitted via WIFI. It is always a multiple of 2kiB that is lost. RTS/CTS is working fine (see attached picture; upper channel is RX, lower channel RTS (both at WIFI-module)). Firmware should be up-to-date; at least I can use ADC command.

Thanks for your help,

Georg

Gerardo GALLUCCI · ‎2015-10-13

Posted on October 13, 2015 at 15:03

Hi Georg,

can you please share a simple use case to help me figuring out what's going wrong?

STA/miniAP, socket server/client, config & status dump, other...

Thanks

jerry

gsiebke · ‎2015-10-13

Posted on October 13, 2015 at 15:38

Status and config:

# Status & Statistics:

# version = 150410-c2e37a3-SPWF01S

# reset_reason = 2

# conf_flag = 5

# system_uptime = 20

# system_sleeptime = 0

# gpio_enable = 0

# captiveportal = 0

# wifi_state = 10

# wifi_bssid = 34:80:B3:D4:67:15

# wifi_aid = 5

# wifi_channelnum = 6

# wifi_sup_rate_mask = 0x003FFFCF

# wifi_bas_rate_mask = 0x0000000F

# wifi_chan_activity2 = 0x00001FFF

# wifi_max_tx_power = 17

# wifi_gf_mode = 0

# wifi_reg_country = DE

# wifi_dtim_period = 2

# wifi_sleeping = 0

# wifi_num_assoc = 0

# ip_ipaddr = 192.168.43.177

# ip_netmask = 255.25Ãœ :00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00

# wifi_ssid_len = 5

# wifi_txfail_thresh = 5

# wifi_ht_mode = 0

# wifi_channelnum = 6

# wifi_opr_rate_mask = 0x00003FCF

# wifi_bas_rate_mask = 0x0000000F

# wifi_mode = 1

# wifi_auth_type = 0

# wifi_atim_window = 0

# wifi_powersave = 0

# wifi_tx_power = 18

# wifi_rssi_thresh = 0

# wifi_rssi_hyst = 0

# wifi_ap_idle_timeout = 120

# wifi_beacon_loss_thresh = 10

# wifi_priv_mode = 2

# wifi_wep_keys[0] = 00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00

# wifi_wep_keys[1] = 00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00

# wifi_wep_keys[2] = 00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00

# wifi_wep_keys[3] = 00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00

# wifi_wep_key_lens = 00:00:00:00

# wifi_wep_default_key = 0

# wifi_wpa_psk_raw = 24:DB:77:EC:C9:64:8A:DC:EC:33:C7:E7:AD:45:4F:90:B5:4F:0A:A8:12:90:CC:FC:DC:9E:58:BF:FA:D6:1D:A6

# wifi_wpa_psk_text = jeufftdgbvysfjk

# ip_use_dhcp = 1

# ip_use_httpd = 1

# ip_mtu = 1500

# ip_hostname = iwm-B5-8A-51

# ip_apdomainname = captiveportal.net

# ip_apredirect = firstset.html

# ip_ipaddr = 192.168.0.50

# ip_netmask = 255.255.255.0

# ip_gw = 192.168.0.1

# ip_dns = 192.168.0.1

# ip_http_get_recv_timeout = 3000

# ip_wait_timeout = 12000

# ip_dhcp_timeout = 20

# ip_sockd_timeout = 5

# Dumping All Configuration Keys:

# nv_manuf = ST

# nv_model = SPWF01SA1

# nv_serial = 2215D28923

# nv_wifi_macaddr = 00:80:E1:B5:8A:51

# blink_led = 0

# wind_off_low = 0x00000000

# wind_off_medium = 0x00000000

# wind_off_high = 0x00000000

# user_desc = anonymous

# escape_seq = at+s.

# localecho1 = 0

# console1_speed = 460800

# console1_hwfc = 1

# console1_enabled = 1

# sleep_enabled = 0

# standby_enabled = 0

# standby_time = 10

# wifi_tx_msdu_lifetime = 0

# wifi_rx_msdu_lifetime = 0

# wifi_operational_mode = 0x00000011

# wifi_beacon_wakeu p_key_lens = 00:00:00:00

# wifi_wep_default_key = 0

# wifi_wpa_psk_raw = 24:DB:77:EC:C9:64:8A:DC:EC:33:C7:E7:AD:45:4F:90:B5:4F:0A:A8:12:90:CC:FC:DC:9E:58:BF:FA:D6:1D:A6

# wifi_wpa_psk_text = jeufftdgbvysfjk

# ip_use_dhcp = 1

# ip_use_httpd = 1

# ip_mtu = 1500

# ip_hostname = iwm-B5-8A-51

# ip_apdomainname = captiveportal.net

# ip_apredirect = firstset.html

# ip_ipaddr = 192.168.0.50

# ip_netmask = 255.255.255.0

# ip_gw = 192.168.0.1

# ip_dns = 192.168.0.1

# ip_http_get_recv_timeout = 3000

# ip_wait_timeout = 12000

# ip_dhcp_timeout = 20

# ip_sockd_timeout = 5

As a test, I'm simply sending 1024 byte blocks without pausing, each consisting of 1024 x the same byte. From block to block, the byte increases by one, so I can check how much is lost. I look for the first and last byte of the block, and they are almost always the same. Additionally, using wireshark I can see that always n x 2kiB are lost.

gsiebke · ‎2015-10-13

Posted on October 13, 2015 at 15:38

The problem occurs in STA as well in MiniAP mode. I'm using socket server.

Gerardo GALLUCCI · ‎2015-10-13

Posted on October 13, 2015 at 16:04

Both in TCP and UDP?

gsiebke · ‎2015-10-13

Posted on October 14, 2015 at 07:27

Problem occurs in both modes. One thing that might be interesting is the packet size. In TCP mode, packets have either 289 or 730 bytes. When data is lost, one packet with 578 bytes is transmitted. In UDP mode, packet size seems constant (1027 bytes). Neither of the values is close to MTU of 1500.

Gerardo GALLUCCI · ‎2015-10-14

Posted on October 14, 2015 at 09:21

MTU is limited when socket server is opened.

Please take a look at this thread:[DEAD LINK /public/STe2ecommunities/interface/Lists/WiFi%20Modules/Flat.aspx?RootFolder=/public/STe2ecommunities/interface/Lists/WiFi%20Modules/Flow%20control%20not%20working%20as%20I%20expect&FolderCTID=0x01200200770978C69A1141439FE559EB459D75800086789498A6852D4897EA192EB1DEE909&TopicsView=https%3a//my.st.com/public/STe2ecommunities/interface/Lists/WiFi%2520Modules/AllItems.aspx&currentviews=57]https://my.st.com/public/STe2ecommunities/interface/Lists/WiFi%20Modules/Flat.aspx?RootFolder=%2fpublic%2fSTe2ecommunities%2finterface%2fLists%2fWiFi%20Modules%2fFlow%20control%20not%20working%20as%20I%20expect&FolderCTID=0x01200200770978C69A1141439FE559EB459D75800086789498A6852D4897EA192EB1DEE909&TopicsView=https%3A%2F%2Fmy%2Est%2Ecom%2Fpublic%2FSTe2ecommunities%2Finterface%2FLists%2FWiFi%2520Modules%2FAllItems%2EaspxÂ¤tviews=57

Message posted on 10/7/2015 1:53 PM

Let me know if it helps

j

gsiebke · ‎2015-10-14

Posted on October 14, 2015 at 09:36

Hi jerry,

flow control seems to work fine, see first post. Concerning the buffer size and timing I'm not sure, what I have to take care of. I would assume that a full buffer leads to an RTS signal, so transmission automatically pauses until the buffer is ready again. Or do I need to somehow check buffer usage?

Gerardo GALLUCCI · ‎2015-10-14

Posted on October 14, 2015 at 09:52

Hi Georg,

correct. Every time buffer is full, RTS stops (should stop) external MCU/PC.

I always see this behaviour, and, so, I'm not able to reploduce data loss using flow control.

I use ST Eval Board (IDW001), and a PC (linux).

gsiebke · ‎2015-10-14

Posted on October 14, 2015 at 10:21

Hi jerry,

with RTS on, a package is lost only within minutes. Disabling RTS leads to about 20% data loss, so I think I can be sure about RTS working fine. I would guess that the problem occurs after UART transmission inside the module.

My SPWF01SA is directly connected to a STM32F4.