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SPI and RS232 question

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Full Member level 5
Oct 22, 2005
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spi to rs232

Is it possible to use the SPI interface to communicate with a MAX232 to enable another USART on a PIC?

spi rs232

Can u pls explain what u want to do ??
SPI is a synchronous comm while RS232 is ASync.
Pls tell with a brief circuit diagram desc.

spi to rs232 converter

...Yest it is possible if you are using an SPI UART like MAX3100... ;-)

spi rs 232

Ya by software it may be possible to emulate rs232 via SPI port but it may be very tough and it will eat up lot of processor computation power it is better to use a SPI to UART chip with built in charge pump like MAX3111 which takes care of the UART functions (but it is costly) and its performance is good as we have tested it in our design and it supports high baud rate. or u can use the processor I/O pins as serial transmitter and receiver.:idea:

spi with rs232

Slayerza said:
Is it possible to use the SPI interface to communicate with a MAX232 to enable another USART on a PIC?

i think your question is not so clear. could you explain in more detail?

SPI and RS232 are totally different.

+interface +pc +spi +max232

OK, just though it might be more effective then bit banging a USART, but if I need onother IC the bit banging part will have to stay. Besides as baud rates are not that high it should possible


your question is not so clear but spi is usually used between integrated pic-pic not pic-rs232 circuits . to set baud rate on spi is quite difficult because the only baud rates in spi are divisions of frequency...maybe 1/4 Osc etc but if you are sending information between two pics then its possible but pic to rs232 using spi is not so possible. i hope that answers your question ...

rs232 + spi

it is possible. but u r question still it is not clear can u explain clearly

spi mit rs232

Revised question. What i want to do is install a Bluetooth (BT) module to facilitate communication with a PC. However, i want to debug the BT setup with a PC as I am then able to basically complete the rest of the project, before implementing the BT.

Thus, by using one of those SPI-UART ICs and a RS232 tranciever (MAX232 say) this can be done?

uart bit bang spi

use max3111 does the same you require.!

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