Post by thread:[SX] UART 115200 with x3 sampling

In SX Microcontrollers, SX/B Compiler and SX-Key Tool, javalin wrote:All, Happy new year!! Quick ISR question; If I want to run an ISR dual uart using 3 times sampling rather than 4 so I can add buffer code to the ISR, would the following figures be correct? SX18 at 50mhz (1/50000000 = 20ns) int_period at 144 (144 * 20ns = 2.88us) baud_rate_divisor at 3 (3 * 144 = 4.32us) baud_rate_start_delay at 4 (4 * 144 = 5.76us - a little short I know) So with a dual uart approach I guess every 3 ISR's I am transmitting and recieving (bar start bits) on one of the uarts. Does this look correct? Many thanks for any help!!

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In SX Microcontrollers, SX/B Compiler and SX-Key Tool, javalin wrote:Ignore my post! Just realized whats wrong!! FYI - Because I am alternatly sampling two uarts alternate uarts are sampled at 2.88us. So each uart is sampled at 5.76us. So I completely miss the sampling in a divisable 8.68us (1/115200) timebase. Doh.

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