BlogpostIt is a known fact that our dotstack™ has the smallest footprint on the market, not to mention dotstack’s easy portability and user friendly API – just see the number of microcontrollers and microprocessors our dotstack™ is running on.
One hot topic these days is an announcement by Texas Instruments that they provide a free stack on several platforms, without any royalties! That is great news for some. However, developers have to be aware that as always in life, nothing is free. Using Texas Instruments’ stack, devleopers will not be able to optimize their firmware to fit in the smallest processor from the family of processors they ideally would want to use.
At SEARAN, we decided to show developers what they can actually expect when using dotstack™ on one of the most popular Cortex M4 processors, STM32F4, in comparison with Texas Instruments’ no royalty solution.
To illustrate the point, we show you two charts. The first one demonstrates two generic Bluetooth BR/EDR user cases, while the second one shows two examples using BLE(GATT) profiles.
In the first table we demonstrate an SPP profile and a streaming audio solution with A2DP and AVRCP profiles while using a Bluetooth controller’s own SBC.
In all examples below we included integration code, FreeRTOS and their code examples for both Texas Instruments and SEARAN. This is a “head-to-head” comparison of both stacks in action.
Certainly, some optimization can be done to RAM and Flash. For example, dotstack™ RAM requirement can be significantly reduced, i.e. to 4KB for SPP or BLE(GATT) profiles if not using FreeRTOS. Nevertheless, data below demonstrates out-of-the-box comparison between SEARAN and Texas Instruments stack requirements.
| TI | SEARAN dotstack™ | TI | SEARAN dotstack™ | ||
| SPP | SPP min configuration | SPP fast configuration | A2DP, AVRCP | A2DP
AVRCP |
|
| Code Memory/Flash (bytes) | 105,773 | 68,845 | 69,889 | 200,169 | 95,451 |
| Read-only Data Memory
(bytes) |
16,351 | 7,754 | 7,754 | 7,424 | 8,399 |
| Read-Write Data Memory
(bytes)
|
66,262 | 11,241 | 25,395 | 66,700 | 22,947 |
When we compare BLE(GATT) profiles the situation is even more advantageous for the dotstack™.
Requirements for Flash are three times greater, and six times higher for RAM when using Texas Instruments’ stack!
Note: Consider that in the table below we compare a single ANP (Alert Notification) profile by Texas Instruments with a combined ANP and PASP (Phone Alert Status) profile by SEARAN.
| TI | SEARAN | TI | SEARAN | |
| ANP | ANP + PASP | Heart Rate, Central | Heart Rate, Central | |
| Code Memory (bytes) | 160,258 | 57,382 | 161,958 | 54,036 |
| Read only Data Memory (bytes) | 23,001 | 7,474 | 11,437 | 7,293 |
| Read-Write Data Memory (bytes) | 66,976 | 11,977 | 66,520 | 12,885 |
These charts above clearly demonstrate that by using dotstack™ and SEARAN software developers would be able to optimize hardware much better, and build the most cost effective solution for the low power applications that IoT devices require these days.