| ??? 08/05/09 09:40 Read: times |
#168167 - CTS latency Responding to: ???'s previous message |
Data drop around CTS timing will occur regardless of the size of the transfer.
FT232BM Designers Guide, Version 2.0 http://www.ftdichip.com/Documents...232_20.pdf "When RTS/CTS hardware handshaking is enabled CTS# can be used to stop the FT232BM transmitting data to the MCU / external logic. When CTS# is active ( low ) the FT232BM will transmit any data in it’s internal buffers. On taking CTS# high, the FT232BM will stop transmitting data. Due to the asynchronous nature of the interface, there is a latency of 0 to 3 characters between taking CTS# high and data transmission stopping. The FT232BM drives RTS# high when the available buffer space inside the device drops below 32 bytes. This allows the MCU / logic to continue to send up to 30 characters to the FT232BM after RTS# goes high without causing buffer over-run." I can't find similar document for current FT232R / FT2232H family on FTDI site. But it's better to assume this behavior is still there. Tsuneo |
| Topic | Author | Date |
| someone a FAQ please | 01/01/70 00:00 | |
| not sure whether FTDI translates to preferable at 921.6kBaud | 01/01/70 00:00 | |
| 921 kBaud to a PC running under Windows | 01/01/70 00:00 | |
| CTS latency | 01/01/70 00:00 | |
| Not just USB? | 01/01/70 00:00 | |
Hardware handshake | 01/01/70 00:00 | |
| Not convinced that HW is the (only) issue | 01/01/70 00:00 | |
| Example | 01/01/70 00:00 | |
| Poor quality | 01/01/70 00:00 | |
| Indeed | 01/01/70 00:00 | |
| hardware (firmware?) | 01/01/70 00:00 | |
| Is FAQ entry working yet? | 01/01/70 00:00 |